SaiBook.us SAT-3

Lesson

Title: Measurment

Grade: Best-SAT3 Lesson: S4-P2

Explanation: Hello students, let us learn a new topic in SAT-3 today with definitions, concepts, examples, and worksheets included.

Lesson:

Definition: Ratios

A ratio is a quantitative relationship between two numbers showing how many times one value contains or is contained within the other.
It is expressed as "a to b" or a/b, where a and b are the two quantities being compared.

*Ratios can also be written with a colon as a:b.

$1$

Explanation: The ratio 500,000:200,000 simplifies to 5:2 when both numbers are divided by their greatest common divisor, which is 100,000.

Definition: Proportion

A proportion is an equation that states that two ratios are equal.
It is a way to express that two sets of quantities have the same relative size or that one quantity is a multiple of the other.
Proportions are written in the form a/b = c/d or a:b=c:d, where a, b, c, and d are numbers, and b and d are not zero.

$2$

Explanation: To find the third proportional number to 9 and 12, assign it the variable x. Use the proportion

9 : 12::12 : x. Cross-multiply to get x = 16. Therefore, the third proportional number is 16.