Quantitative Aptitude - Arithmetic Ability Questions

Let the present age of Ravali = x

=> Swarna's present age = x - 9

From the given data,

x + 7 = 2(x - 9 + 7)

=> x = 11 yrs

Required Ravali's age after 4 years = 11 + 4 = 15 yrs.

sin 46. cos 44+ cos 46. sin 44

sin 46. sin (90 -44)+ cos 46. cos (90 -44)

= sin^2 46 + cos^2 46

= 1

I = prt = [15000 × 0.07 × (214/365) ]=615.52

Future value, S = P + I = $15 000 + $615.52 = $15 615.52

Let the required number be 'p'

36 of what number is 18 implies 36% of p = 18

=> 36 x p/100 = 18

=> p = 1800/36

=> p = 50.

Hence, 36% of 50 is 18.

As water costs free, water sold at cost price of milk gives the profit.

Required profit % = 5/20 x 100 = 5 x 5 = 25%.

Ans.
Given that length of first train + length of second train = 660
Speed of first train : Speed of second train = 5:8 =5x : 8x
Time taken to cross the poll by two trains = 4:3 =4y:3y
Now ,
(5x*4y) + (8x*3y) = 660
44xy = 660
xy = 15
L1 - L2 = 24xy -20xy = 4xy = 60 m

The given series is 15, 19, 27, 38, 55, 75

15

15 + 4 = 19

19 + 8 = 27

27 + 12 = 39

39 + 16 = 55

55 + 20 = 75

Hence, the odd number in the given series is 38.

Let S be the sample space and E be the event of selecting 1 girl and 2 boys.

Then, n(S) = Number ways of selecting 3 students out of 25

                = 25C3  = 2300.

         n(E)= 10C1*15C2 = 1050. 

P(E) = n(E)/n(s) = 1050/2300 = 21/46