Find the least square number, exactly divisible by each one of the numbers: (i) 6,9, 15 and 20) (ii) 8,12, 15 and 20

(i) 6, 9, 15 and 20

L.C.M of given 4 numbers is 180


180 = 22 × 32 × 5


To make it a perfect square, we have to multiply the number with 5


Therefore,


180 × 5 = 22 × 32 × 52


900 is the least square number divisible by 6, 9, 15 and 20


3600 is the least square number divisible by 8, 12, 15 and 20


(ii) 8, 2, 15 and 20


L.C.M of given 4 numbers is 360


360 = 22 × 32 ×2 × 5


To make it a perfect square, we have to multiply the number with 2 × 5 = 10


Therefore,


360 × 10 = 22 × 32 × 52 × 22


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