EXERCISE 7A (OBJECTIVE TYPE QUESTIONS IN 11 15 SOLUTION )

11.       If one-seventh of a number exceeds its eleventh part by 100, then the number is:

a)      770

b)      1100

c)       1825

d)      1925

12.       If the sum of one-half and one-fifth of a number exceeds one-third of that number by 7 ½, the number is:

a)      15

b)      18

c)       20

d)      30

13.       If doubling a number and adding 20 to the result gives the same answer as multiplying the number by 8 and taking away 4 from the product, the number is:

a)      2

b)      3

c)       4

d)      6

14.       If 50 is subtracted from two-third of a number, the result is equal to sum of 40 and one-fourth of that number. What is the number?

a)      174

b)      216

c)       246

d)      336

15.       If the sum of a number and its square is 182, what is the number?

a)      15

b)      26

c)       18

d)      91

e)      None of these

ANSWERS

11.D

12.C

13.C

14.B

15.E

 SOLUTION 

11.       Let the number be x. then, 1/7X – 1/11x = 100   4X/77 = 100  X = 7700 / 4

             = 1925.

12.       Let the number be x.

                Then, (12 X + 1/5 x ) – 1/3 X = 22 / 3  11x /30 = 22 ./ 3     x = (22 x 30 /3 x 11)

                   = 20.

13.       Let the number be x. then, 2x + 20 = 8x – 4    6x = 24    

             X = 4.

14.       Let the number be x.

                Then, 2/3X – 50 = ¼ X + 40   2/3 X = 1/4X = 90    5x / 12 = 90     X = (90 x 12 /5) 

                = 216.

15.       Let the number be X.

                Then, x + x² = 182   x² + X – 182 = 0  ( X + 14) (X – 13) = 0   X = 13.

                X = 13.