Mathematical operations

Directions for Q. No. 1 to 6 : If ‘+’ is ‘×’ , ‘-’ is ‘+ ; ‘×’ is ‘÷’ and ‘÷’ is ‘-’, then answer the following questions based on this information.

1.         21 ÷ 8 + 2 - 12 × 3 = ?

(a) 14            (b) 9                 (c) 13.5         (d) 11               (e) None

2.         6 + 7 × 3 - 8 ÷ 20 = ?

(a) -3                                      (b) 7              (c) 2                  (d) 1        (e) None

3.         15 × 5 ÷ 3 + 1 -1 = ?

(a) - 1            (b) - 2               (c) 3              (d) 1                 (e) None

4.         9 - 3 + 2 ÷ 16 × 2 = ?

(a) 7              (b) 5                 (c) 9              (d) 6                 (e) None

5.         6 - 9 + 8 × 3 ÷ 20 = ?

(a) -2                                      (b) 6              (c) 10               (d) 12     (e) None

6.         9 ÷ 5 + 4 - 3 × 2 = ?

(a) 2              (b) - 9               (c) - 3            (d) 8                 (e) None

Directions for Q. No. 7 to 11: If the given interchanges are made in signs and numbers, which one of the four equations would be correct?

7.         Given interchanges: signs ‘+’ & ‘-’ ; numbers ‘5’ and ‘8’.

(a) 82 - 35 + 55 = 2              (b) 82 - 35 + 55 = 102        

(c) 85 - 38 + 85 = 132  (d) 52 - 35 + 55 = 72

8. Given interchanges: signs ‘+’ & ‘×’ ; numbers ‘3’ and ‘7’.

(a) 23 + 17 × 73 = 1241      (b) 37 + 73 × 12 = 112       

(c) 23 × 17 + 37 = 428        (d) 23 + 17 x 73 = 388

9.         Given interchanges: signs ‘×’ & ‘÷’ ; numbers ‘4’ and ‘9’.

(a) 94 × 7 ÷ 47 = 329          (b) 94 × 7 ÷ 97 = 329         

(c) 49 × 7 = 49 = 7       (d) 47 × 9 ÷ 94 = 18

10.      Given interchanges: signs ‘-’ & ‘÷’ ; numbers ‘2’ and ‘6’.

(a) 32 - 12 ÷ 6 = 30              (b) 36 ÷ 12 - 2 = 1               

(c) 32 - 16 ÷ 6 = 1                (d) 36 - 12 ÷ 2 = 30

 

11.      Given interchanges: signs ‘+’ & ‘×’; numbers ‘1’ and ‘3’.

(a) 31 + 34 × 31 = 1085      (b) 31 + 34 × 31= 195

(c) 13 + 34 × 13 = 195        (d) 31 + 14 × 13 = 213

Directions for Q. No. 12 to 14: In the following questions :

          D means ‘is equal to’

          b means ‘is not equal to’

          + means ‘is greater than’

          - means ‘is less than’

          × means ‘is not greater than’

          ÷ means ‘is not less than’

Now, select the correct alternative in each of the following questions :

12.      a - b - c implies

(a) a - b + c (b) b + a - c     (c) c × b + a    (d) b + a ÷ c   (e) None

13.      a + b - c implies

(a) b - c - a   (b) c - b + a     (c) c + b - a  (d) c × b ÷ a    (e) None

14.      a × b ÷ c implies

(a) a - b + c  (b) c × b ÷ a    (c) a b b b c  (d) b ÷ a ÷ c    (e) None

Answers

1. (b)         2. (c)           3. (d)           4. (a)             5. (c)           6. (e)  

7. (a)         8. (d)           9. (b)           10. (c)           11. (b)        12. (b)

13. (c)       14. (b)