Belajar Matematika dan Bisnis Online

IXL Math On IXL, math is more than just numbers. With unlimited questions, engaging item types, and real-world scenarios, IXL helps learners experience math at its most mesmerizing! Pre-K skills Represent numbers - up to 5 Inside and outside Classify shapes by color Long and short Wide and narrow See all 77 pre-K skills Kindergarten skills Fewer, more, and same Read clocks and write times Seasons Count money - pennies through dimes Shapes of everyday objects I See all 182 kindergarten skills First-grade skills Counting tens and ones - up to 99 Hundred chart Subtraction facts - numbers up to 10 Read a thermometer Measure using an inch ruler See all 210 first-grade skills Second-grade skills Counting patterns - up to 1,000 Greatest and least - word problems - up to 1,000 Compare clocks Create pictographs II Which customary unit of volume is appropriate? See all 287 second-grade skills Third-grade skills Convert between standard and expanded form Count equal groups Estimate sums Show fractions: area models Find equivalent fractions using area models See all 384 third-grade skills Fourth-grade skills Addition: fill in the missing digits Divide larger numbers by 1-digit numbers: complete the table Objects on a coordinate plane Circle graphs Place values in decimal numbers See all 340 fourth-grade skills Fifth-grade skills Least common multiple Multiply fractions by whole numbers: word problems Sale prices Find start and end times: word problems Parts of a circle See all 347 fifth-grade skills Sixth-grade skills Compare temperatures above and below zero Which is the better coupon? Evaluate variable expressions with whole numbers Classify quadrilaterals Create double bar graphs See all 321 sixth-grade skills Seventh-grade skills Solve percent equations Arithmetic sequences Evaluate multi-variable expressions Identify linear and nonlinear functions Pythagorean theorem: word problems See all 289 seventh-grade skills Eighth-grade skills Write variable expressions for arithmetic sequences Add and subtract polynomials using algebra tiles Add polynomials to find perimeter Multiply and divide monomials Scatter plots See all 317 eighth-grade skills Algebra 1 skills Write and solve inverse variation equations Write an equation for a parallel or perpendicular line Solve a system of equations by graphing Solve a system of equations using substitution Rational functions: asymptotes and excluded values See all 309 Algebra 1 skills Geometry skills Triangle Angle-Sum Theorem Proving a quadrilateral is a parallelogram Properties of kites Similarity of circles Perimeter of polygons with an inscribed circle See all 221 Geometry skills Algebra 2 skills Multiply complex numbers Product property of logarithms Find the vertex of a parabola Write equations of ellipses in standard form from graphs Reference angles See all 322 Algebra 2 skills Precalculus skills Identify inverse functions Graph sine functions Convert complex numbers between rectangular and polar form Find probabilities using two-way frequency tables Use normal distributions to approximate binomial distributions See all 261 Precalculus skills Calculus skills Find limits using the division law Determine end behavior of polynomial and rational functions Determine continuity on an interval using graphs Find derivatives of polynomials Find derivatives using the chain rule I See all 97 Calculus skills Mathematics is a persistent source of difficulty and frustration for students of all ages. Elementary students spend years trying to master arithmetic. Teens struggle with the shift to algebra and its use of variables. High-school students must face diverse challenges like geometry, more advanced algebra, and calculus. Even parents experience frustration as they struggle to recall and apply concepts they had mastered as young adults, rendering them incapable of providing math help for their children. Whether you need top Math tutors in Boston, Math tutors in Detroit, or top Math tutors in Dallas Fort Worth, working with a pro may take your studies to the next level. The truth is, everyone struggles with math at one time or another. Students, especially at the high-school level, have to balance challenging coursework with the demands of other courses and extracurricular activities. Illness and school absences can leave gaps in a student’s instruction that lead to confusion as more advanced material is presented. Certain concepts that are notoriously difficult to master, such as fractions and the basics of algebra, persist throughout high school courses, and if not mastered upon introduction, can hinder a student’s ability to learn new concepts in later courses. Even students confident in their math skills eventually find a course or concept incomprehensible as they reach advanced math classes. In other words, no matter what your age or ability, everyone eventually needs help with math. Varsity Tutors offers resources like free Math Diagnostic Tests to help with your self-paced study, or you may want to consider a Math tutor. Varsity Tutors is happy to offer free practice tests for all levels of math education. Students can take any one of hundreds of our tests that range from basic arithmetic to calculus. These tests are conveniently organized by course name (e.g. Algebra 1, Geometry, etc.) and concept (e.g. “How to graph a function”). Students can select specific concepts with which they are struggling or concepts that they are trying to master. Students can even use these concept-based practice tests to identify areas in which they may not have realized they were struggling. For instance, if a student is struggling with his or her Algebra 1 course, he or she can take practice tests based on broad algebra concepts such as equations and graphing and continue to practice in more specific subcategories of these concepts. In this way, students can more clearly differentiate between those areas that they fully understand and those that could use additional practice. Better yet, each question comes with a full written explanation. This allows students to not only see what they did wrong, but provides the student with step-by-step instructions on how to solve each problem. In addition to the Math Practice Tests and Math tutoring, you may also want to consider taking some of our Math Flashcards. Varsity Tutors’ Learning Tools also offer dozens of Full-Length Math Practice Tests. The longer format of the complete practice tests can help students track and work on their problem-solving pace and endurance. Just as on the results pages for the concept-specific practice tests, the results for these longer tests also include a variety of scoring metrics, detailed explanations of the correct answers, and links to more practice available through other Learning Tools. These free online Practice Tests can assist any student in creating a personalized mathematics review plan, too, as the results show which of the concepts they already understand and which concepts may need additional review. After reviewing the skills that need work, students can take another Full-Length Math Practice Test to check their progress and further refine their study plan. Once a student creates a Learning Tools account, they can also track their progress on all of their tests. Students can view their improvement as they begin getting more difficult questions correct or move on to more advanced concepts. They can also share their results with tutors and parents, or even their math teacher. Create a Varsity Tutors Learning Tools account today, and get started on a path to better understanding math!

Materi Perbandingan Kelas 7

Hai adik-adik, kita akan belajar materi perbandingan. Dalam kehidupan sehari-hari sering terdapat hal-hal yang berkaitan dengan perbandingan. Misalnya,
  • Berat badan Ari lebih dari berat badan Tedy.
  • Uang Nia besarnya 2 kali uang Diah.
  • Umur Nisa kurang dari umur Tias
  • dsb.
Apa yang akan kita bandingkan adalah besaran yang sama dari dua atau beberapa benda yang berbeda. Ada besaran panjang, massa, waktu, dan sebagainya. Kalian harus tahu satuan dari masing-masing besaran tersebut beserta cara konversi satuannya. karena jika satuan dari besarannya berbeda maka harus disamakan dulu. Misalnya, panjang A adalah 1 m dan panjang B 30 cm. Kita dapat menyatakan panjang A adalah 100 cm sehingga kita dapat membandingkan panjang A dengan panjang B. 

Dua Cara Membandingkan Besaran

Ada dua cara dalam membandingkan besaran, yakni dengan menentukan selisih dan menentukan rasio (hasil bagi) sehingga dari contoh yang diberikan, kita dapat membandingkan panjang A dan B sbb.
  1. Menggunakan selisih dimana diketahui selisih dari panjang A dan panjang B adalah 70cm. Misalnya, "Panjang A 70 cm lebihnya dari panjang B". 
  2. Menggunakan rasio dimana diketahui panjang A dan panjang B memiliki rasio $10 : 3$ dari penyederhanaan $\frac{100}{30}$. Misalnya, "Panjang A adalah $\frac{10}{3}$ kali dari panjang B".

Rasio adalah perbandingan dua bilangan  a dan b yang dinotasikan sebagai $a : b$ atau $\frac{a}{b}$ atau a berbanding b. Pernyataan dua rasio yang sama atau ekuivalen disebut proporsi, yaitu $a : b = c : d$. 

Perbandingan Senilai dan Berbalik Nilai

Ada dua macam dalam perbandingan, yaitu perbandingan senilai (proporsi) dan perbandingan berbalik nilai. Misalnya diketahui perbandingan dengan rasio $a : b$ senilai dengan perbandingan dengan rasio $c : d$ maka disebut perbandingan senilai dan dinyatakan dengan $a : b = c : d$ sedagkan jika berbalik nilai maka disebut perbandingan berbalik nilai dan dinyatakan dengan $a : b = \frac{1}{c} : \frac{1}{d}$ atau $a : b = d : c$.

Misalkan $x$ dan $y$ adalah variabel, jika untuk setiap nilai dari $x$ yang berpadanan dengan nilai $y$ sehingga x : y memiliki rasio yang sama atau tetap maka disebut perbandingan senilai. Jika $x$ banding $y$ adalah $\frac{x}{y} = \frac{1}{k}$ dimana k adalah konstan maka disebut perbandingan berbalik nilai dan $k$ disebut konstanta perbandingan.

Beberapa masalah perbandingan senilai:
  • Jika harga 4 kg beras adalah Rp. 36.000, berapa harga 8 kg beras?
  • Jujun berlari dengan kecepatan 3 kali lebih cepat daro Joni. Jika jarak yang ditempuh Jujun 9km, berapakah jarak yang ditempuh Joni?
  • Es jeruk manakah yang lebih asam, 2 takar sirup dicampur dua gelas air putih atau 3 takar sirup dicampur dua gelas air putih?
  • Perbandingan senilainya adalah  $4 : 8 = 36.000 : x$ atau $\frac{4}{8}=\frac{36.000}{x}$ sehingga nilai x dapat dicari dengan $x = \frac{8×36.000}{4} = 72.000$. Jadi, harga 8kg beras adalah Rp. 72.000,-
  • Rasio kecepatan lari Jujun dan Joni adalah $3 : 1$ sehingga perbandingan senilainya adalah $\frac{3}{1} = \frac{9}{x}$, maka $x= \frac{9}{3}=3$.
  • Lebih asam 3 takar sirup dicampur dua gelas air putih.
Beberapa masalah bukan perbandingan senilai:
  • Saat Budi berusia 4 tahun, adiknya berusia 2 tahun. Sekarang usia Budi 8 tahun, berapakah usia adiknya?
  • Es jeruk manakah yang lebih asam, 2 takar sirup dicampur dengan dua cangkir air putih atau 3 bungkus takar sirup dicampur dengan dua cangkir air putih?
  • Ini bukanlah masalah perbandingan senilai, tetapi masalah selisih umur Budi dan adiknya dimana usia adik Budi saat Budi berusia 8 tahun adalah 6 tahun.
  • Bukan masalah perbandingan senilai karena yang dibandingkan berbeda dan tidak bisa ditentukan takarannya antara 2 takar sirup dan 3 bungkus takar sirup.
Beberapa masalah perbandingan berbalik nilai:
  • 5 sapi dapat menghabiskan rumput seluas 5 are dalam 5 hari. Berapakah hari yang diperlukan bagi 10 sapi untuk menghabiskan rumput seluas 5 are tersebut?
  • 2 orang pekerja dapat menyelesaikan kerjaan dalam 4 hari. Jika kerjaan tersebut harus diselesaikan dengan dua hari saja, berapakah semua pekerja yang dibutuhkan?
  • 5 sapi dapat menghabiskan rumput tersebut selama 5 hari. Semakin banyak sapi maka semakin sedikit hari yang dihabiskan sehingga ini merupakan masalah perbandingan berbalik nilai, yaitu $\frac{5}{10}= \frac{x}{5}$ maka diperoleh $x= \frac{5×5}{10} = \frac{25}{10}=2,5$. Jadi, jumlah hari yang diperlukan adalah 2,5 hari.
  • Diserahkan kepada pembaca.

Skala adalah perbandingan antara ukuran gambar dan ukuran sebenarnya. Skala sering kita temui pada peta, denah, miniatur kendaraan, dan sebagainya. Skala ditemui juga pada termometer suhu, antara lain skala Celcius (°C), skala Reamur (°R), skala Fahrenheit (°F) yang dinyatakan dengan perbandingan C : R : (F-32) = 5 : 4 : 9. Lihat cara perbandingan termometer yang satu dengan termometer yang lain pada Perbandingan Termometer Celcius, Fahrenheit, dan Kelvin.

Soal dan Jawaban
  1. Soal No. 1 dst. Ayo Kita Berlatih 5.1 (Memahami  dan Menentukan Perbandingan Dua Besaran).
  2. Soal No. 1 dst. Ayo Kita Berlatih 5.2 (Menentukan Perbandingan Dua Besaran dengan Satuan yang Berbeda).
  3. Soal No. 1 dst. Ayo Kita berlatih 5.3 (Memahami dan Menyelesaikan Masalah yang Terkait dengan Perbandingan Senilai).
  4. Soal No. 1 dst. Ayo Kita berlatih 5.4 (Menyelesaikan Masalah Perbandingan Senilai pada Peta dan Model).
  5. Soal No. 1 dst. Ayo Kita berlatih 5.5 (Memahami dan Menyelesaikan Masalah yang Terkait dengan Perbandingan Berbalik nilai).
Materi lanjutan setelah Perbandingan adalah Materi Aritmatika Sosial Kelas 7, semoga bermanfaat.

Berlangganan Update Artikel Terbaru via Email:

No comments:

Post a Comment

Komentar yang tidak baik atau menampilkan segala hal yang tidak baik, tidak akan kami setujui atau akan kami hapus!

Ebook Berhitung Tanpa Meminta

Kontak Kami


Email *

Message *

Copyright © Matematika Ku Bisa. All rights reserved. Template by CB. Theme Framework: Responsive Design