mcqs Math Percentage 55 is what percent of 90? Or, What percent of 90 is equal to 55? 1186

Question: 55 is what percent of 90? Or, What percent of 90 is equal to 55?

(A)  76.39%
(B)  45.83%
(C)  61.11%
(D)  91.67%

Correct Answer 61.11%

Solution And Explanation

Solution

Given number = 90

To find, 55 is what percent of 90?

This question can be written as also

What percent of 90 is equal to 55?

⇒ ?% of 90 = 55

Let ? = m

And the meaning of "of" in mathematics is "Multiplication".

∴ m% of 90 = 55

⇒ m% × 90 = 55

⇒ ^m/₁₀₀ × 90 = 55

⇒ ^{90 m}/₁₀₀ = 55

After cross multiplication, we get

90 m = 55 × 100

After transposing 90 to RHS, we get

m = ^{55 × 100}/₉₀

⇒ m = ⁵⁵⁰⁰/₉₀

⇒ m = 61.11%

Thus, 61.11% of 90 = 55

Thus, Answer = 61.11%

If we have to find

? % of a = b

Here, let ? = m

Thus, above expression can be written as

m% of a = b

⇒ ^m/₁₀₀ × a = b

⇒ ^{m × a}/₁₀₀ = b

After cross multiplication, we get

m × a = b × 100

⇒ m = ^{b × 100}/_a

Thus, using this formula, we can find a number (a) is what (m) percent of b

In the question, we have to find what percent of 90 = 55

Here, we have ? = m

a = 90

And, b = 55

Thus, using formula

⇒ m = ^{55 × 100}/₉₀

= ^{55 × 100}/₉₀

= ⁵⁵⁰⁰/₉₀ = 61.11%

Thus, 61.11% of 90 = 55

Thus, 61.11% Answer