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If 56 Workers Can Build a Wall in 180 Hours, How Many Workers Will Be Required to Do the Same Work in 70 Hours?

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Question

If 56 workers can build a wall in 180 hours, how many workers will be required to do the same work in 70 hours?

Sum
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Solution

Workers: Hours:: Workers: Hours

   56     :    180  ::     x       :   70

∴ By inverse proportion

56 × 180 = x × 70

`⇒"x"=(180xx56)/70`

= 144 workers

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Chapter 10: Direct and Inverse Variations - Exercise 10 (B) [Page 123]

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Selina Concise Mathematics [English] Class 8 ICSE
Chapter 10 Direct and Inverse Variations
Exercise 10 (B) | Q 7 | Page 123

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