Quantitative Aptitude - Arithmetic Ability Questions

Interest earned in scheme M =   

P1 + 201002 - 1 = 11P25

Interest earned in scheme N =  

P x k x 2100 = Pk50

Now, from the given data,

11P25 = 2 x Pk50

k = 11

Here the given series 7  18  42  94  204 follows a pattern that, 

7

7 ×2+4 = 18

18 ×2+6 = 42

42 ×2+10 = 94

94 ×2+16 = 204

Similarly,

4

4 ×2+4 = 12

12 ×2+6 = 30

30 ×2+10 = 70

70 ×2+16 = 156

Hence, the value of P = 156.

If the Multiples for two or more numbers which are Common, then those Multiples are said to be Common Multiples. 

For Example :

Multiples of 3 are 3, 6, 9, 12, 15, 18, 21, 24, 27, 30,...

Multiples of 5 are 5, 10, 15, 20, 25, 30,...

Here common multiples of 3 & 5 upto 30 are 15, 30.

Let the speed of the slower train = p kmph

ATQ,

Speed of the faster train = (p + 6) kmph

Then,

(p + p + 6) x 5 = 160

10p + 30 = 160

10p = 130

p = 13 kmph

Then, speed of the faster train = p + 6 = 13 + 6 = 19 kmph.

Age of new boy = (Age of moved girl) – (Number of family members × Decreased in average)

= 24 – 24×4/12

= 24 – 8

= 16 years.

Total engineers = 4800

Number of female engineers = 3/8 x 4800 = 1800

Then, number of male engineers = 4800 - 1800 = 3000

Now, required is female engineers is what percentage of the number of male engineers

=> 1800 is what % of 3000

=> p x 3000/100 = 1800

=> 30p = 1800

p = 60%

Hence, female engineers is 60 percentage of the number of male engineers.

P.W. = Rs. (1600 - 160) = Rs. 1440
∴ S.I. on Rs.1440 at 5% is Rs. 160.
∴ Time = [100 * 160 / 1440 * 5] = 20/9 years = [20/9 * 12] months = 27 months.