Exercise 3 Page 881

When adding or subtracting fractions, they should have the same denominator. In this exercise, we have two fractions with different denominators. 2/5 + 7/8 Now, we can factor both of the denominators to find any common factors. 5= 5 and 8=2(2)(2) There are no common factors. Therefore, the common denominator is equal to 5( 8) or 40. Now, we can multiply both numerator and denominator of each fraction by the factors that do not occur in their denominators.

2/5 + 7/8

ExpandFrac

a/b=a * 8/b * 8

2( 8)/5( 8) + 7/8

ExpandFrac

a/b=a * 5/b * 5

2(8)/5(8) + 7( 5)/8( 5)

Multiply

Multiply

16/40 + 35/40

Now that we have a common denominator, we can proceed to simplifying the expression.

16/40 + 35/40

▼

Add fractions

AddFrac

Add fractions

16+35/40

AddTerms

Add terms

51/40

The quotient is 5140. We can also write this fraction as a mixed number.

51/40

▼

Write as a sum of fractions

WriteSum

Write as a sum

40+11/40

WriteSumFrac

Write as a sum of fractions

40/40+11/40

CalcQuot

Calculate quotient

1+11/40

AddTerms

Add terms

111/40