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2. The table given below shows how much Varun spent on some items.

Round off each amount Item Amount in (`)
to the nearest thousand New car 6,29,575
and estimate: Washing machine 28,675

Mobile phone 36,435
Air pod 3,970

(a) total amount spent on washing machine and mobile phone.
(b) the difference of the cost of washing machine and the cost of air pod.

(c) total amount spent by Varun.
3. Find the estimated quotient of 3,25,870 and 8,543.
4. Find the actual and the estimated sum of 4,83,479 and 5,67,891 by rounding off to
the nearest 10,000.
5. Find the actual and the estimated product of 1,439 × 784.

6. If 23,52,167 votes were cast in the constituency A election, whereas 30,14,184 votes
were cast in the constituency B election. Estimate the difference between the votes
cast in these two constituencies.

SIMPLIFICATION OF NUMERICAL EXPRESSIONS

We have already learnt how to perform arithmetic operations (addition, subtraction,

multiplication and division) to the numbers.
But sometimes we need to solve an expression which Remember
contains more than one operation; we can get different Numbers connected together
results depending on the order in which the operations by one or more operations
are carried out. form a numerical expression.

Let us simplify 5 + 5 + 45 ÷ 5 × 4 – 1

Possibility 1 Possibility 2 Possibility 3
= (5 + 5 + 45) ÷ 5 × 4 – 1 = 5 + 5 + 45 ÷ 5 × (4 – 1) = (5 + 5 + 45 ÷ 5) × 4 – 1

[Add first three numerals] [Subtract: 4 – 1 = 3 ] [Divide: 45 ÷ 5 = 9]
= 55 ÷ (5 × 4) – 1 = 5 + 5 + 45 ÷ (5 × 3) = (5 + 5 + 9) × 4 – 1

[Multiply: 5 × 4 = 20] [Multiply: 5 × 3 = 15] [Add: 5 + 5 + 9 = 19]
= 55 ÷ (20 – 1) = (5 + 5 + (45 ÷ 15) = (19 × 4) – 1

[Subtract: 20 – 1 = 19] [Divide: 45 ÷ 15 = 3] [Multiply: 19 × 4 = 76]
= 55 ÷ 19 = 5 + 5 + 3 = 76 – 1

[Divide: 55 by 19 = 2 17 ] [Add: 5 + 5 + 3 = 13] [Subtract: 76 – 1 = 75]
19
= 2 17 = 13 = 75
19

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