Question

If decreasing 70 by x% yields the same result as increasing 60 by x%, then x% of 91 is:
1. 7
2. 6
3. 8
4. 5

Answer 1

Correct Answer - Option 1 : 7

Given:          

If decreasing 70 by x% yields the same result as increasing 60 by x%

Concept used:

1% = 1/100

Calculation:

According to the question,

70[1 – (x/100)] = 60[1 + (x/100)]

⇒70[100 – x]/100 = 60[100 + x]/100

⇒ 70[100 – x] = 60[100 + x]

⇒ 7000 – 70x = 6000 + 60x

⇒ 1000 = 130x

⇒ x = 1000/130 

So x% of 91 = [(1000/130)/100] × 91 = 7

∴ The x% of 91 is 7.