Add 36/70 and 54/21, Solve 36/70 + 2 12/21 as a fraction

Add 36/70 and 54/21

1^st number: 36/70, 2^nd number: 2 12/21

36/70 + 54/21 is 108/35.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 70 × 3 = 210,
36/70 = 36 × 3/70 × 3 = 108/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
54/21 = 54 × 10/21 × 10 = 540/210
Add the two like fractions:
108/210 + 540/210 = 108 + 540/210 = 648/210
648/210 simplified gives 108/35
So, 36/70 + 54/21 = 108/35
In mixed form: 33/35

MathStep (Works offline)

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