mcqs Math Percentage 50 is what percent of 80? Or, What percent of 80 is equal to 50? 1185

Question: 50 is what percent of 80? Or, What percent of 80 is equal to 50?

(A)  78.13%
(B)  46.88%
(C)  62.5%
(D)  93.75%

Correct Answer 62.5%

Solution And Explanation

Solution

Given number = 80

To find, 50 is what percent of 80?

This question can be written as also

What percent of 80 is equal to 50?

⇒ ?% of 80 = 50

Let ? = m

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

∴ m% of 80 = 50

⇒ m% × 80 = 50

⇒ ^m/₁₀₀ × 80 = 50

⇒ ^{80 m}/₁₀₀ = 50

After cross multiplication, we get

80 m = 50 × 100

After transposing 80 to RHS, we get

m = ^{50 × 100}/₈₀

⇒ m = ⁵⁰⁰⁰/₈₀

⇒ m = 62.5%

Thus, 62.5% of 80 = 50

Thus, Answer = 62.5%

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 80 = 50

Here, we have ? = m

a = 80

And, b = 50

Thus, using formula

⇒ m = ^{50 × 100}/₈₀

= ^{50 × 100}/₈₀

= ⁵⁰⁰⁰/₈₀ = 62.5%

Thus, 62.5% of 80 = 50

Thus, 62.5% Answer