Add 5/4 and 7/42, Solve 1 1/4 + 7/42 as a fraction

Add 5/4 and 7/42

1^st number: 1 1/4, 2^nd number: 7/42

5/4 + 7/42 is 17/12.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 42 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 4 × 21 = 84,
5/4 = 5 × 21/4 × 21 = 105/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
7/42 = 7 × 2/42 × 2 = 14/84
Add the two like fractions:
105/84 + 14/84 = 105 + 14/84 = 119/84
119/84 simplified gives 17/12
So, 5/4 + 7/42 = 17/12
In mixed form: 15/12

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad