Find the smallest number by which 147 must be multiplied so that it becomes a perfect square. Also, find the square root of the number so obtained.
147 = 72 × 3
To make the unpaired 3 into paired, multiply the number with 3
Therefore,
147 × 3 = 72 × 32
Hence, square root of number = 
= 7 × 3
= 21
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