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\ 10-Nov-2025 Bharat Arora Proof-8 Reader’s Sign _______________________ Date __________

Exercise 3F

1. Estimate the following products by rounding each number to the nearest 10.

a. 14 × 36 = ____ b. 75 × 33 = ____ c. 44 × 41 = ____

d. 78 × 82 = ____ e. 42 × 68 = ____ f. 53 × 31 = ____

g. 397 × 26 = ____ h. 154 × 18 = ____ i. 327 × 46 = ____

j. 263 × 124 = ____ k. 127 × 268 = ____ l. 133 × 527 = ____

2. Estimate the following products by rounding each number to the nearest 100.

a. 109 × 267 = _____ b. 445 × 123 = _____ c. 198 × 364 = _____

d. 176 × 248 = _____ e. 325 × 278 = _____ f. 190 × 127 = _____

g. 235 × 168 = _____ h. 154 × 356 = _____ i. 204 × 320 = _____

WorD ProBlEMS

Example 1. A box contains 144 mangoes.

Find the number of mangoes in 208 such boxes. TTh Th H T O
1 4 4
Solution. Number of mangoes in a box = 144
× 2 0 8
Number of boxes = 208
1 1 5 2
Number of mangoes in 208 boxes = 144 × 208 0 0 0 0
= 29952 + 2 8 8 0 0

Therefore, the total number of mangoes in 208 boxes 2 9 9 5 2
is 29952.

Example 2. The price of an earring is `64.

Find the total cost of 99 earrings. Th H T O

Solution. Cost of an earring = `64 6 4
Number of earrings = 99 × 9 9

Cost of 99 earrings = `64 × 99 5 7 6
= `6336 + 5 7 6 0

Therefore, the total cost of 99 earrings is `6336. 6 3 3 6

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Multiplication