Quantitative Aptitude - Arithmetic Ability Questions

The given number series is 3, 12, 39, 120, 364

$$\begin{gathered} 3 \\ 3 + 32 = 3 + 9 = 12 \\ 12 + 33 = 12 + 27 = 39 \\ 39 + 34 = 39 + 81 = 120 \\ 120 + 35 = 120 + 243 = 363 (Not 364) \end{gathered}$$

A:B:C = (10×7):(12×5):(15×3)

         = 70 :60 :45

         = 14 :12 :9

C's rent = Rs.(175×9/35)

            =Rs. 45.

The series follows the following pattern.

4

16 = 42

37 = 12+62

58 = 32+72

81 ≠52+82.

Here every number is based on the digits of previous number. Hence, 81 is the wrong number in the given series.

The given number series 2676, 445, ?, 21,6, 2, 1 follows a pattern that,

From right side,

1

1 x 1 + 1 = 2

2 x 2 + 2 = 6

6 x 3 + 3 = 21

21 x 4 + 4 = 88

88 x 5 + 5 = 445

445 x 6 + 6 = 2676

Hence the missing number in the given number series is 88.

Let S.P. of 45 lemons be Rs. x.

Then, 80 : 40 = 120 : x or   x = 40×12080= 60

For Rs.60, lemons sold = 45

For Rs.24, lemons sold  =4560×24= 18.

Area of the park = (60 x 40) = 2400m2

Area of the lawn = 2109m2 

Area of the crossroads = (2400 - 2109) = 291m2 

Let the width of the road be x metres. Then,

60x+40x-X2=291 

x2-100x+291=0 

  (x - 97)(x - 3) = 0
   x = 3.