... 150.¹

$17\times 9 -3=150$

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... 92.²

$(25-2)\times 4=92$

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... 91.³

Sanju's age $\times 7=91$.

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... 16.⁴

Sanju's marks $/6=16$.

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... 55.⁵

Raju's weight $\times 2+5=55$.

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... colleges)¹

Writing down such equations and the ability to manipulate them is important in other areas also, such as commerce and economics.

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... manner.²

Many real weighing machines are in fact based on this principle.

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... correct.³

If the extension turned out to be different it would mean that our equation is incorrect, which in turn would mean that Hooke's law is incorrect or our first observation is incorrect.

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