## Mathematical operation and symbol notation

#### Mathematical operation and symbol notation

1. Select the correct combination of mathematical signs to replace * signs and to balance the given equation.
5 * 6 * 5 * 8 * 14

1. 5 x 6 ÷ 5 + 8 = 14

##### Correct Option: B

5 x 6 ÷ 5 + 8 = 14

1. If + = x , - = ÷ , x = + , ÷ = - , then which is the correct equation out of the following ?

1. 18 + 6 - 4 x 2 ÷ 3 = 26
After chaning, the equation is
L.H.S., 18 x 6 ÷ 4 + 2 - 3
108 ÷ 4 + 2 - 3
27 + 2 - 3
29 - 3 = 26 R.H.S.

##### Correct Option: B

18 + 6 - 4 x 2 ÷ 3 = 26
After chaning, the equation is
L.H.S., 18 x 6 ÷ 4 + 2 - 3
108 ÷ 4 + 2 - 3
27 + 2 - 3
29 - 3 = 26 R.H.S.

1. If + means ÷, - means x, x mean +, ÷ means -, then
90 + 18 - 6 x 30 ÷ 4 = ?

1. 65

##### Correct Option: B

65

Direction: In each of the following questions, all the equations except one have been solved according to a certain rule. You are required to solve the unsolved equation following the same rule and to choose the correct answer out of the given options.

1. 9 * 7 = 32, 13 * 7 = 120, 17 * 9 = 208, 19 * 11 = ?

1. As, 9 * 7 ⇒ (9 + 7) (9 - 7) = 16 x2 = 32
13 * 7 ⇒ (13 + 7) (13 - 7) = 20 x 6 = 120
17 * 9 ⇒ (17 + 9) (17 - 9) = 26 x 8 = 208

##### Correct Option: C

As, 9 * 7 ⇒ (9 + 7) (9 - 7) = 16 x2 = 32
13 * 7 ⇒ (13 + 7) (13 - 7) = 20 x 6 = 120
17 * 9 ⇒ (17 + 9) (17 - 9) = 26 x 8 = 208
Similarly, 19 * 11 ⇒ (19 + 11) (19 - 11) = 30 x 8 = 240
∴ ? = 240

1. 4 - 4 = 12, 6 - 6 = 30, 2 - 2 = 2, 8 - 8 = ?

1. As, 4 - 4 ⇒ 4 x 4 - 4 = 12
6 - 6 ⇒ 6 x 6 - 6 = 30
2 - 2 ⇒ 2 x 2 - 2 = 2

##### Correct Option: C

As, 4 - 4 ⇒ 4 x 4 - 4 = 12
6 - 6 ⇒ 6 x 6 - 6 = 30
2 - 2 ⇒ 2 x 2 - 2 = 2
Similarly, 8 - 8 ⇒ 8 x 8 - 8 = 56