Quantitative Aptitude - Arithmetic Ability Questions

For ticking 6 times, there are 5 intervals.

Each interval has time duration of 30/5 = 6 secs

At 12 o'clock, there are 11 intervals,
so total time for 11 intervals = 11 x 6 = 66 secs.

Total student= 39, boys : girls = 2:1, hence no of boys= 2/3(39)= 26
num of girls= 1/3(39) = 13 , since radhika ranked 15 among 39 student from top
and ranked 8 among girls from bottom , this means 7 girls are below radhika, rest 13-9= 5 girls are above her, now from 14 toper 5 are girls hence 14-5=9 boys.
Hence num of boys below radhika are 26-9=17

Let a and b are the numbers.Then a+b is 12 and ab is 35.

a+b/ab = 12/35

1/b + 1/a = 12/35

Last digit for the power of 6 is 6 (always)

Power cycle of 7 is 7, 9, 3, 1.

Now 467/4 gives a remainder of 3

Then the last digit is 73 = 3

Last digit is 6 + 3 = 9.

(kx5x1)/100 + [(1500 - k)x6x1]/100 = 85

5k/100 + 90 – 6k/100 = 85

k/100 = 5

=> k = 500

let the radius of the pool be Rft

Radius of the pool including the wall = (R+4)ft

Area of the concrete wall = πR+42-R2=πR+4+RR+4-R = 8πR+2 sq feet

=> 8πR+2 = 1125πR2 =>11R2 =200R+2

Radius of the pool R = 20ft

Let current ages of X and Y correspondingly, is 6A & 5A
Given: 6A + 5A = 44
=> A = 4
Proportion of ages after 0.8 decades will be
6A + 8 : 5A + 8   32:28 (or) 8:7

Possibilities     Bowlers      Batsmen         Number of ways

                         6               9

         1              4                7              (6C4*9C7)

         2              5                6              6C5*9C6

         3              6                5              6C6*9C5

6C4*9C7 = 15 x 36 = 540

6C5*9C6 = 6 x 84 = 504

 6C6*9C5= 1 x 126 = 126

Total = 1170