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Find the number of zeroes at the end of the product of (4144 – 4143 – 4141) (5140 – 5139 – 5138).1. 1382. 2843. 4224. None of these |
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Answer» Correct Answer - Option 1 : 138 Given: Expression is (4144 – 4143 – 4141) (5140 – 5139 – 5138) Concept used: To find the number of zeroes at the end of the product, we need to calculate the number of 2’s and number 5’s or number of pairs of 2 and 5. 2 × 5 = 10 ⇒ Number of zeroes = 1 (number of pair = 1) The number of pairs of 2 and 5 is same as the number of zeroes at the end of the product Calculation: (4144 – 4143 – 4142) (5140 – 5139 – 5138) ⇒ 4142 (42 – 41 – 40) × 5138 (52 – 51 – 50) ⇒ 4142 (16 – 4 - 1) × 5138 (25 – 5 - 1) ⇒ 4142 × 11 × 5138 × 19 ⇒ (22)142 × 11 × 5138 × 19 ⇒ 2284 × 11 × 5138 × 19 In the above expression, number of 5’s is less than the number of 2’s. So there are only 138 pairs of 2 and 5 are possible, number of zeroes would be 138 ∴ The total number of zeroes at the end of the product is 138. |
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