Quantitative Aptitude - Arithmetic Ability Questions

P can complete the work in (12 x 8) hrs = 96 hrs 

Q can complete the work in (8 x 10) hrs=80 hrs 

Therefore, P's 1 hour work=1/96   and Q's 1 hour work= 1/80

(P+Q)'s 1 hour's work =(1/96) + (1/80) = 11/480. So both P and Q will finish the work in 480/11 hrs  

Therefore, Number of days of 8 hours each = (480/11) x (1/8) = 60/11

Here the given number series is 6, 3, 3, 4.5, 10

The odd one in the given series is 10

The pattern it follows is

6

6 x 0.5 = 3

3 x  1  = 3

3 x 1.5 = 4.5

4.5 x 2 = 9

Hence, the odd number is 10.

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.

The terms of the series are products of two consecutive prime numbers i.e.

(2 x 3), (3 x 5), (5 x 7), (7 x 11),.....

So, 165 is wrong and must be replaced by (11 x 13) i.e. 143.

Here the given series is 1, 3, 6, 11, 20, 37, ??,

and the logic behind the series is

1 x 2 + 1 = 3

3 x 2 + 0 = 6

6 x 2 + (-1) = 11

11 x 2 + (-2) = 20

20 x 2 + (-3) = 37

37 x 2 + (-4) = 70

Hence, the next number in the given series is 70.

Let the numbers be a and b.

Then, a + b = 55 and ab = 5 x 120 = 600.

The required sum =1a+1b = a+bab= 55600=11120

The pattern followed is +3 , +6 , +12 , +24 , +48

A:B:C = (10×7):(12×5):(15×3)

         = 70 :60 :45

         = 14 :12 :9

C's rent = Rs.(175×9/35)

            =Rs. 45.