Question

a:b=1:2 what is the valu of 3(a-b)=?

Answer 1

a/b = 1:2

Now:

a=2b

b=a/2

So:

3(a-b)

=3(2b-b)

==>3b

Or

3(a-b)

=3(a-a/2)

=3*1/2a

=3/2a

Hope it helps

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Answer 2

a:b=1:2

So

$\frac{a}{b} =\frac{1}{2} \\2a=b\\b=2a$

3(a-b)=3(a-2a)=3(-a)=-3a

Hope this helps:)