A reduction of 10% in the price of an apple enable a man to buy 10 apples more for Rs. 54. The reduced price of apples per dozen is :
(A) Rs. 6.48
(B) Rs. 12.96
(C) Rs. 10.80
(D) Rs. 14.40
Solution:
Let initial expenditure = 100 units Required increment = = 1 unit = 10 apples Original consumption = 9 units = 9 × 10 = 90 apples New consumption = 10 units = 10 × 10 = 100 apples New price = × 12 = Rs. 6.48 per dozen
552.
In the price of sugar falls by , a person can buy 9 kg more of sugar for Rs. 1260 than before. If the price had risen by , how much sugar would he have bought for the same sum ?
(A) 288 kg
(B) 312 kg
(C) 328 kg
(D) 336 kg
Solution:
Let the original price of sugar be Rs. per kg Then, reduced price : Increased price : ∴ Quiantity of sugar bought for Rs. 1260 :
553.
In an examination it is required to get 36% of the aggregate marks to pass. A student gets 198 marks and is declared failed by 36 marks. What is the maximum aggregate marks a student can get ?
(A) 480
(B) 550
(C) 650
(D) Cannot be determined
Solution:
Let the maximum marks be x Then, 36% of x = 198 + 36 ⇒ = 234 ⇒ x = ⇒ x = 650
554.
If 120 is 20% of a number, then 120% of that number will be :
(A) 20
(B) 120
(C) 480
(D) 720
Solution:
Let the number = x According to the question, x × = 120 x = 600 Required answer = 600 × = 720 Alternate 20% represents → 120 1% → So, 120% = × 120 = 720
555.
The length, breadth and height of a room are in ratio 3:2:1. If breadth and height are halved while the length is doubled, then the total area of the four walls of the room will
(A) remain the same
(B) decrease by 13.64%
(C) decrease by 15%
(D) decrease by 18.75%
Solution:
Answer & Solution Answer: Option E Solution: Let length, breadth and height of the room be 3, 2, 1 unit respectively. Area of walls = 2(l + b) × h = 2(3 + 2) × 1 = 10 sq. unit. Now, length, breadth and height of room will become 6, 1 and respectively. Now, area of walls = = 7 sq. unit. % decrease in the area of walls = = 30%
556.
A and B are two fixed points 5 cm apart and C is a point on AB such that AC is 3 cm. If the length of AC is increased by 6%, the length of CB is decreased by :
(A) 6%
(B) 7%
(C) 8%
(D) 9%
Solution:
Original length of AB = 5 cm Original length of AC = 3 cm Original length of CB = (5 - 3) cm = 2 cm New length AC : = 106% of 3 cm = cm = 3.18 cm New length of CB : = (5 - 3.18) cm = 1.82 cm Decrease in length of CB : = (2 - 1.82) cm = 0.18 cm ∴ Decrease % : = = 9%
557.
80% of a smaller number is 4 less than 40% of a larger number. The larger number is 85 greater than the smaller one. The sum of these two number is
(A) 325
(B) 425
(C) 235
(D) 500
Solution:
Let the smaller number be x and larger number be y According to the question, 80% of x + 4 = 40% of y 4y - 8x = 40 y - 2x = 10 --------- (1) y - x = 85 ----------- (2) By using (1) and (2), we get x = 75 y = 160 x + y = 235
558.
If A is equal to 20% of B and B is equal to 25% of C. Then what percentage of C equal to A ?
(A) 10%
(B) 15%
(C) 5%
(D) 20%
Solution:
A = 20% of B A = B ----(i) B = 25% of C B = C ----(ii) Multiply (i) and (ii) We get Percent of C is equal to A
559.
In an examination, 35% of total students failed in Hindi, 45% failed in English and 20% failed in both. Find the percentage of those students who passed in both the subjects ?
(A) 45%
(B) 35%
(C) 20%
(D) 40%
Solution:
Failed students in Hindi = 35% Failed students in English = 45% Student failed in both subject hindi and english = 20% Student only fail in hind = 35 - 20 = 15% Student only fail in English = 45 - 20 = 25% Percentage of passed students in both subjects : = 100 - [ student fail in hindi + student fail in english + student fail in both subject] = [100 - (15 + 25 + 20)] = 40%
560.
A shepherd had n goats in the year 2000. In 2001 the no. of goats increased by 40%. In 2002 the no. of goats declined to 70%. In 2003 the no. of goats grew up 30%. In 2004, he sold 10% goats and then he had only 34,398 goats. The percentage increase of the no. of goats in this duration was :
(A) 16.66%
(B) 14.66%
(C) 11.33%
(D) 20%
Solution:
There is no need of the number of goats given i.e. 34,398. Initially, let there be 100 goats. Then 100 == 40% ↑==> 140 == 30%↓(declined to 70%) ==> 98 == 30%↑ ==> 127.4 == 10%↓(sold) ==> 114.66 Hence, % increase = 14.66% [As 100 becomes 114.66]