Add 70/21 and 6/40, Solve 3 7/21 + 6/40 as a fraction

Add 70/21 and 6/40

1^st number: 3 7/21, 2^nd number: 6/40

70/21 + 6/40 is 209/60.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 21 × 40 = 840,
70/21 = 70 × 40/21 × 40 = 2800/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
6/40 = 6 × 21/40 × 21 = 126/840
Add the two like fractions:
2800/840 + 126/840 = 2800 + 126/840 = 2926/840
2926/840 simplified gives 209/60
So, 70/21 + 6/40 = 209/60
In mixed form: 329/60

MathStep (Works offline)

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