Question

Find the sum of
-6 1/8+1 1/4

Answer 1

`\large\boxed{-4(7)/(8)=-4.875}`

Explanation:

To add two fractions, they must have the same denominator.

LCD = 8

`1(1)/(4)=1(1\cdot2)/(4\cdot2)=1(2)/(8)`

`-6(1)/(8)+1(1)/(4)=-6(1)/(8)+1(2)/(8)=-\left(6(1)/(8)-1(2)/(8)\right)=(*)\\\\\text{We know}\ 1=(8)/(8),\ 6=5+1=5+(8)/(8)=5(8)/(8).\\\\\text{Therefore}\ 6(1)/(8)=5(8+1)/(8)=5(9)/(8)\\\\(*)=-\left(5(9)/(8)-1(2)/(8)\right)=-\bigg((5-1)+(9-2)/(8)\bigg)=-\bigg(4+(7)/(8)\bigg)=-4(7)/(8)`

You can convert the fractions to the decimals.

`6(1)/(8)=8.125\\\\1(1)/(4)=1.25\\\\-6(1)/(8)+1(1)/(4)=-6.125+1.25=1.25-6.125=-4.875`