7th Grade Math

338 Percent

Find the Percent

21 is what percent of 40?

Estimate _^2140 ≈^1 _ 2 or 50%

part = percent · whole

21 = n · 40 Write the percent equation.

_^21

40

= _^40 n

40

Divide each side by 40.

0.525 = n Simplify.

Since n represents the decimal form, the percent is 52.5%.

So, 21 is 52.5% of 40.

Check for Reasonableness 52.5% ≈ 50% ✓

Write an equation for each problem. Then solve. Round to the

nearest tenth if necessary.

c. 35 is what percent of 70? d. What percent of 125 is 75?

e. What percent of 40 is 9? f. 27 is what percent of 150?

Find the Whole

13 is 26% of what number?

Estimate _^14 of 48 = 12

part = percent · whole

13 = 0.26 · w Write the percent equation. 26% = 0.26

_^13

0.26

= _0.26w

0.26

Divide each side by 0.26.

50 = w Simplify.

So, 13 is 26% of 50.

Check for Reasonableness 50 is close to 48. ✓

Write an equation for each problem. Then solve. Round to the

nearest tenth if necessary.

g. 39 is 84% of what number? h. 26% of what number is 45?

i. 14% of what number is 7? j. 24 is 32% of what number?

Percent Percent Remember to

write the decimal as a

percent in your final

answer.

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