Quantitative Aptitude - Arithmetic Ability Questions

Given a x a = 12

asked to find a x a x a x a =  (a x a) x (a x a)

a⁴ = a² x a² 

= 12 x 12

= 144.

More :: Mathematical operations questions and answers.

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.

let ABCD be the given parallelogram 

area of parallelogram ABCD = 2 x (area of triangle ABC) 

now a = 30m, b = 14m and c = 40m

 s=1/2 x (30+14+40) = 42 

Area of triangle ABC = ss-as-bs-c  

= 4212282= 168sq m 

area of parallelogram ABCD = 2 x 168 = 336 sq m

Suppose the can initially contains 7x and 5x litres of mixtures A and B respectively

Quantity of A in mixture left =7x-712×9=7x-214 litres.

Quantity of B in mixture left =  5x-512×9=5x-154litres.

7x-2145x-154+9=79

⇒28x-2120x+21=79

⇒x=3

 So, the can contained 21 litres of A.

Here the given series follows a pattern that, multiplying the number with odd numbers in decreasing order starting with 13. That is,

6 × 13 = 78

65 × 11 = 858

858 × 9 = 7722

7722 × 7 = 54054

54054 × 5 = 270270

Hence, the wrong number is 54055

87)13601(156
       87
       -----
       490
       435
        -----
        551
        522
         -----
         29
         -----
Required number is 29.

Required number of ways = (7C5*3C2) = (7C2*3C1) = 63