Percentage - Study Mode
[#421] A report consists of 20 sheets each of 55 lines and each such line consist of 65 characters. This report is reduced onto sheets each of 65 lines such that each line consists of 70 characters. The percentage reduction in number of sheets is closer to
Correct Answer
(A) 20%
Explanation
Solution: Let x be the page required when report is retyped Now, we can use work equivalence method 20 × 55 × 65 = 70 × 65 × x Or, x = $$frac{{20 imes 55 imes 65}}{{70 imes 65}}$$ Or, x = 15.70 = 16 pages. Hence, % reduction in pages = $$left( {20 - 16}
ight) imes frac{{100}}{{20}}$$ xa0 $$, = ,$$ $$20\% $$
[#422] The price of Maruti car rises by 30 percent while the sales of the car come down by 20%. What is the percentage change in the total revenue?
Correct Answer
(C) + 4%
Explanation
Solution: Let initial price of Maruti Car be Rs. 100 As price increases 30%, price of car will become, (100 + 30% of 100) = Rs. 130 Due to increase in price, sales is down by 20%. It means, it is going make 20% less revenue as expected after increment of price So, New revenue = (130 - 20% of 130) = Rs. 104 The initial revenue was Rs. 100 which becomes Rs. 104 at the end. It means there is 4% increment in the total revenue Mind Calculation Method: 100 == 30%↑(price effect) ==> 130 == 20%↓(sales effects) ==> 104 Hence, 4% rises
[#423] 1.14 expressed as a percent of 1.9 is :
Correct Answer
(C) 60%
Explanation
Solution: Required percentage : $$eqalign{
& = left( {frac{{1.14}}{{1.9}} imes 100}
ight)\% cr
& = left( {frac{{114}}{{190}} imes 100}
ight)\% cr
& = 60\% cr} $$
[#424] 42% of a number is 892.5. What is 73% of that number ?
Correct Answer
(C) 1551.25
Explanation
Solution: Let the number be x Then, $$eqalign{
& 42\% ,,{ ext{of}},,x = 892.50 cr
& Rightarrow frac{{42x}}{{100}} = 892.50 cr
& Rightarrow x = left( {frac{{892.5 imes 100}}{{42}}}
ight) cr
& Rightarrow x = 2125 cr
& herefore 73\% ,,{ ext{of}},,2125 cr
& = left( {frac{{73}}{{100}} imes 2125}
ight) cr
& = 1551.25 cr} $$
[#425] A toy merchant announces 25% rebate in prices of balls. If one needs to have a rebate of Rs. 40, then how many balls each costing Rs. 32, he should purchase ?
Correct Answer
(A) 5
Explanation
Solution: Rebate on one ball : = 25% of Rs. 32 = Rs. $$left( {frac{{25}}{{100}} imes 32}
ight)$$ = Rs. 8 ∴ Required number of balls : = $$frac{40}{8}$$ = 5