## Mathematical operation and symbol notation

#### Mathematical operation and symbol notation

1. If '+' means 'minus', '-' means 'multiply', '÷' means 'plus' and 'x' means 'divide', then 10 x 5 ÷ 3 - 2 + 3 = ?
1. 5
2. 53/3
3. 21
4. 36

1. ? = 10 x 5 ÷ 3 - 2 + 3
As per question
= 10 ÷ 5 + 3 x 2 - 3

Apply the rule BODMAS

B -Brackets first
O -Orders (i.e. Powers and Square Roots, etc.)
DM -Division and Multiplication (left-to-right)

##### Correct Option: A

? = 10 x 5 ÷ 3 - 2 + 3
= 10 ÷ 5 + 3 x 2 - 3
Apply the rule BODMAS
Do things in Brackets First
(Powers, Roots) before Multiply, Divide, Add or Subtract.
Multiply or Divide before you Add or Subtract
= 10 ÷ 5 + 3 x 2 - 3
= 2 + 3 x 2 - 3
= 2 + 6 - 3
Subtraction
= 8 - 3 = 5

1. If "T" means (x), 'U' means (-) , 'X' means (÷) and W means (+), then what will be the value of the following expression ?

(50 X 2) W (28 T 4 )
1. 142
2. 158
3. 137
4. 163

1. Given expression, (50 x 2) W (28 T 4)
After interchanging the letters with symbols, we get
(50 ÷ 2) + (28 x 4)

##### Correct Option: C

Given expression, (50 x 2) W (28 T 4)
After interchanging the letters with symbols, we get
(50 ÷ 2) + (28 x 4) = 25 + 112 = 137

1. Select the correct combination of mathematical signs to replace the * signs and to balance the given equation.
40 * 2 * 4 * 3 * 8
1. + - ÷ =
2. ÷ + = x
3. + ÷ x =
4. + x - =

1. Given, 40* 2* 4 * 3 * 8
Let us check all the options one by one.
From option (a), putting the signs in given equation, we get
40 + 2 - 4 ÷ 3
= 8 ⇒ 42 - 4/3 = 8
⇒ 126 - 4 = 24 ⇒ 122 = 24
∴ L H S ≠ R H S
So, option (a) is incorrect.
From option (b), putting the signs in given equation, we get
40 ÷ 2 + 4 = 3 x 8
⇒ 20 + 4 = 24 ⇒ 24 = 24

##### Correct Option: B

Given, 40* 2* 4 * 3 * 8
Let us check all the options one by one.
From option (a), putting the signs in given equation, we get
40 + 2 - 4 ÷ 3
= 8 ⇒ 42 - 4/3 = 8
⇒ 126 - 4 = 24 ⇒ 122 = 24
∴ L H S ≠ R H S
So, option (a) is incorrect.
From option (b), putting the signs in given equation, we get
40 ÷ 2 + 4 = 3 x 8
⇒ 20 + 4 = 24 ⇒ 24 = 24
LHS = RHS
Hence, option (b) is correct and there is no need to check remaining options.

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. 4 - 4 = 17, 6 - 6 = 37, 2 - 2 = 5, 5 - 5 = ?
1. 27
2. 26
3. 20
4. 24

1. As, 4 - 4 ⇒ 4 x 4 + 1 = 17
6 - 6 ⇒ 6 x 6 + 1 = 37

##### Correct Option: B

As, 4 - 4 ⇒ 4 x 4 + 1 = 17
6 - 6 ⇒ 6 x 6 + 1 = 37
2 - 2 ⇒ 2 x 2 + 1 = 5
Similarly, 5 - 5 ⇒ 5 x 5 + 1 = 26
∴ ? = 26

1. If S means '-', Q means 'x' , R means '÷' and P means '+' then
1   P   45   R   2   Q   2   S   4 = ?
1. 40
2. 42
3. 36
4. 46
5. 38

1. After replacing the sign according to question
1   P   45   R   2   Q   2   S   4
= 1 + 45 ÷ 2 x 2 - 4

##### Correct Option: B

After replacing the sign according to question
1   P   45   R   2   Q   2   S   4
Apply the BODMAS Rule
= 1 + 45 ÷ 2 x 2 - 4
= 1 + 22.5 x 2 - 4
= 1 + 45 - 4 = 42