If Five Sevenths of a Number is 15 What is the number?

If Five Sevenths of a Number is 15 What is the number?

If five sevenths of a number is 15, we can solve for the number by setting up the equation:

(5/7) * x = 15

To find x, we multiply both sides by the reciprocal of (5/7), which is (7/5):

x = 15 * (7/5)

x = 21

So, the number is 21.

Solving Problems Involving Fractions of a Number

Word problems commonly involve determining an unknown original number based on a clue involving a fractional amount of that number. For example, if you know 5/7 of a number is 15, you can algebraically determine the full number. Let’s look at the step-by-step process.

Understand the Relationship

The first step is to analyze what we know:

• 5/7 of the number is 15
• We want to find the original number

So we’re looking for the number that gives 15 when 5/7 of it is taken.

Set Up an Equation with a Variable

Using a variable like x to represent the unknown number, we can express the relationship mathematically:

(5/7)x = 15

The fraction 5/7 multiplied by x gives the fractional amount 15.

Isolate the Variable

To isolate x, we multiply both sides by 7/