Add 75/10 and 4/21, Solve 7 5/10 + 4/21 as a fraction

Add 75/10 and 4/21

1^st number: 7 5/10, 2^nd number: 4/21

75/10 + 4/21 is 323/42.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
75/10 = 75 × 21/10 × 21 = 1575/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
4/21 = 4 × 10/21 × 10 = 40/210
Add the two like fractions:
1575/210 + 40/210 = 1575 + 40/210 = 1615/210
1615/210 simplified gives 323/42
So, 75/10 + 4/21 = 323/42
In mixed form: 729/42

MathStep (Works offline)

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