Q131 of 142 Page 88

Find the smallest square number divisible by each one of the numbers 8, 9 and 10.

Given:

the least square number which is exactly divisible by 8, 9 and 10 is equal to L.C.M. 0f 8, 9 and 10.


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Hence, their L.C.M. is 2× 2× 2× 3× 3× 5 = 360


As we see, (2× 2)× 2× (3× 3) × 5


i.e. 2 and 5 is not able to make their pair.


Hence, to make it perfect square, it must be multiplied with 2 × 5 = 10


As, 360× 10 = 3600


Hence 3600 is least square number which is exactly divisible by 8, 9 and 10.


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