Question

HCF(320, x) = 20, LCM(320, x) = 2240, then x =

Answer 1

Answer:

  140

Step-by-step explanation:

When working HCF and LCM problems, I like to think in terms of this little diagram:

  (a [ b ) c]

It shows me one of the numbers is ab, the other is bc, the HCF is b and the LCM is abc. "a" and "c" must be relatively prime for "b" to be the HCF.

__

Here, we're given ...

  b = 20

  ab = 320

  abc = 2240

Then ...

  c = abc/(ab) = 2240/320 = 7

  x = bc = 20(7) . . . . . . equivalently, x = (abc·b)/(ab) = (2240·20)/320

  x = 140