Question 189380
1.m/12= 86
m = 12*86
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2.1/2m =6
m = 2*6
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3. 4z =16
z = 16/4
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4. 4-(2/9) = (20/27)

Multiply both sides by 27 to get:
4*27 - 2*3 = 20
28 - 6 = 20
22 = 20
I think something is missing in your post of this problem
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Cheers,
Stan H.