How do you evaluate #7\frac { 3} { 4} + 1\frac { 7} { 8}#?

2 Answers
Sep 26, 2017

See a solution process below:

Explanation:

First, convert the mixed numbers to improper fractions

#7 3/4 + 1 7/8 =>#

#(7 + 3/4) + (1 + 7/8) =>#

#([4/4 xx 7] + 3/4) + ([8/8 xx 1] + 7/8) =>#

#(28/4 + 3/4) + (8/8 + 7/8) =>#

#(28 + 3)/4 + (8 + 7)/8 =>#

#31/4 + 15/8#

Next, put the fractions over a common denominator by multiplying the fraction on the left by the appropriate form of #1#:

#(2/2 xx 31/4) + 15/8 =>#

#(2 xx 31)/(2 xx 4) + 15/8 =>#

#62/8 + 15/8 =>#

#(62 + 15)/8 =>#

#77/8#

Now, if necessary, convert the improper fraction to a mixed number:

#(72 + 5)/8 =>#

#72/8 + 5/8 =>#

#9 + 5/8 =>#

#9 5/8#

Sep 26, 2017

=#9\frac {5} { 8} #

Explanation:

#7\frac { 3} { 4} + 1\frac { 7} { 8}#

Write in improper form:

=#\frac { 7\times 4 +3} { 4} + \frac { 1\times 8 + 7} { 8}#

=#\frac { 28 +3} { 4} + \frac { 8+ 7} { 8}#

=#\frac {31} { 4} + \frac { 15} { 8}#

Make the denominators equal:

=#\frac {31} { 4}*(2/2) + \frac { 15} { 8}#

=#\frac {62} {8} + \frac { 15} { 8}#
Add:

=#\frac {77} { 8} #

=#9\frac {5} { 8} #