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Neha needs to stretch some sticks to 252 times their original lengths, but her (× 25) machine is broken. Find a hook-up of two repeater machines that will do the same work as a (× 252) machine. - Mathematics

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Question

Neha needs to stretch some sticks to 252 times their original lengths, but her (× 25) machine is broken. Find a hook-up of two repeater machines that will do the same work as a (× 252) machine. To get started, think about the hookup you could use to replace the (× 25) machine.

Sum

Solution

Work done by single machine (× 252) = 25 × 25 = 625 or 5 × 5 × 5 × 5 or 52 × 52

Hence, (× 52) and (× 52) hook-up machine can replace the (× 25) machine.

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Chapter 8: Exponents and Powers - Exercise [Page 271]

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NCERT Exemplar Mathematics [English] Class 8
Chapter 8 Exponents and Powers
Exercise | Q 162. | Page 271

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