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Symbols and Notations

In this chapter, we solve the expression while converting symbols with the actual mathematical characters of the mathematical expression into instructions.

In the examination, mathematical expressions are given with ‘+’, ‘-‘, ‘×’, ‘-‘ or “P” or “Q” or such other signs. The candidates have to solve the changed expression by changing the signs as per the instructions given in the question.



There is a very common rule in solving these types of questions, which is called the rule of BODMAS. This rule is used in most of the questions. So let’s know this rule.

(i) B → Bracket
(ii) O → Of
(iii) D → Division
(iv) M → Multiplication
(v) A → Addition
(vi) S → Subtraction

This rule is called BODMAS Rule, in which we learn the order of solving mathematical expressions, that is, the first ‘Bracket’ then ‘Of’ then division, then ‘multiplication’ then ‘addition’ and  ‘subtraction’ is used in end.

Let us now look at the questions in the examination on the basis of the above facts.

Example 1. If “+” means ‘×’, ‘-‘means “+” and ‘×’ means ‘÷’, then What will be the value of → 5 + 4 – 18 × 3 ?

(a) 26 (b) 14 (c) 34 (d) 6

Solution:
(a) 5 + 4 – 18 × 3
→ 5 × 4 + 18 ÷ 3

5 × 4 + 6 [first division is performed]
20 + 6 = 26 [multiplication then adding.]

Example 2. If ‘K’ displays ‘÷’, “+” is displayed by “V” by ‘-‘ by ‘S’ and ‘× ‘ by “W” , Then what will be the value of 24 V 16 K 8 W 6 S 9?
(a) 21 (b) 25 (c) 27 (d) 29

Solution: (c) Expression given = 24 V 16 K 8 W 6 S 9
According to the question, after changing the mathematical symbols, 24 + 16 ÷ 8 × 6 – 9

→ 24 + 12 – 9 = 36 – 9 = 27

Example 3. In the given equation, To reach the answer given, which option would be appropriate ?
31 4 2 1 = 30

(a) × ÷ × (b) – + ÷ (c) + – × (d) – ÷ +

Solution: (d)
31 – 4 ÷ 2 + 1
31 – 2 + 1 = 32 – 2 = 30







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