Add 15/4 and 72/70, Solve 3 3/4 + 1 2/70 as a fraction

Add 15/4 and 72/70

1^st number: 3 3/4, 2^nd number: 1 2/70

15/4 + 72/70 is 669/140.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 70 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 4 × 35 = 140,
15/4 = 15 × 35/4 × 35 = 525/140
Likewise, for the 2nd fraction, since 70 × 2 = 140,
72/70 = 72 × 2/70 × 2 = 144/140
Add the two like fractions:
525/140 + 144/140 = 525 + 144/140 = 669/140
So, 15/4 + 72/70 = 669/140
In mixed form: 4109/140

MathStep (Works offline)

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