Quantitative Aptitude - Arithmetic Ability Questions

The given number series is 125,   138,   164,   ?,   255

125

125 + 13x1 = 138

138 + 13x2 = 164

164 + 13x3 = 203

203 + 13x4 = 255

Hence, the missing number in the series is 203.

From the given statements A, B & C

Let the present age of Teja = P

Raju present age = P + 4

Sita's present age = 2(P + 4)

Average of ages of Sita & Teja = 19

=> (2P + 8 + P)/2 = 19

= 3P + 8 = 38

=> P = 30/3 = 10

Hence, the present age of Teja = P = 10 yrs.

Therefore, by using all the three statements A, B & C we can find the age of Teja.

Here in the given series, it follows a pattern that

77 + 2 = 79

79  - 3 = 76

76 + 5 = 81

81 -  7 = 74

74 + 11 = 85

Consecutive adding and subtracting of prime numbers.

So the wrong number in the given series is 75.

4       30       ?     1440       7195      71940

Here the given series follows a pattern of

4

4 x 10 - 10 = 30

30 x 5 - 5  = 145

145 x 10 - 10 = 1440

1440 x 5 - 5 = 7195

7195 x 10 - 10 = 71940

Hence, the missing number is 145

Principal = Rs100×540012×3=Rs. 15000

Friends, we know we will need gain amount to get gain percent, right. So lets get gain first.

Let the cost price of 1 pen is Re 1

Cost of 8 pens = Rs 8

Selling price of 8 pens = 12

Gain = 12 - 8 = 4

Gain% = gaincost×100%  = 48×100% = 50%