Question 205958
(1) x*y =600
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(2) (x*y)/ n = 60,,,,,subst  in (1)
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n*60 = 600,,,,,n=10
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x=20,,,y=30,,,LCD  (30),,,,,,60,, ,90,,,......
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,,,,,,,,,,,,,,,,,,,(20),,40,,60,,80,,100,,......
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Therefore  LCD  of 20,30  is  60
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HCF = 20,,,2*2*5
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,,,,,,30,,,2*3*5,,,,,,,HCF = 2*5 =10
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