Quantitative Aptitude - Arithmetic Ability Questions

 x = 80 % of y  

=> x =(80/100 )y  

=> y/x = 5/4  

Required percentage =  [(y/2x)*100] % = (5/8*100) % =62.5%

The given number series 2676, 445, ?, 21,6, 2, 1 follows a pattern that,

From right side,

1

1 x 1 + 1 = 2

2 x 2 + 2 = 6

6 x 3 + 3 = 21

21 x 4 + 4 = 88

88 x 5 + 5 = 445

445 x 6 + 6 = 2676

Hence the missing number in the given number series is 88.

The given number series is 152, 124, 96, 69, 40

152

152 - 28 = 124

124 - 28 = 96

96 - 28 = 68 (not 69)

68 - 28 = 40

Hence, the odd man in the given number series is 69.

Let the normal speed be x km/h, then 

80x-80(x+4)=1

⇒x2+4x-320=0

⇒x (x + 20) - 16 (x + 20) = 0

(x + 20 ) (x - 16) =0

x = 16 km/h

 Therefore (x + 4) = 20 km/h

 Therefore increased speed = 20 km/h

           Wine                         Water

            8L                              32L

            1                :               4

           20 %                           80% (original ratio)

           30 %                           70% (required ratio)

In  ths case, the percentage of water being reduced when the mixture is being replaced with wine.

so the ratio of left quantity to the initial quantity is 7:8

Therefore , 78=1-K40

=> K = 5 Lit

The given number series 100, 101, 97, 105, 90

100

100 + 1^2 = 101

101 - 2^2 = 97

97 + 3^2 = 106 ( not 105)

106 - 4^2 = 90

Hence, the odd man in the given series is 105.

45/100×400+√?=56/100 ×750 -40/100 ×350

180 + √? = 420 - 140 180 + √? = 280 √? = 280 - 180 √? = 100 ? = 1002 ? = 10000

Ratio of rates of working of A and B =2:1. So, ratio of times taken =1:2

Therefore, A's 1 day's work=1/9 

B's 1 day's work=1/18 

(A+B)'s 1 day's work= 1/9 + 1/18 = 1/6

so, A and B together can finish the work in 6 days