Add 30/42 and 15/9, Solve 30/42 + 1 6/9 as a fraction

Add 30/42 and 15/9

1^st number: 30/42, 2^nd number: 1 6/9

30/42 + 15/9 is 50/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 9 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
30/42 = 30 × 3/42 × 3 = 90/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
15/9 = 15 × 14/9 × 14 = 210/126
Add the two like fractions:
90/126 + 210/126 = 90 + 210/126 = 300/126
300/126 simplified gives 50/21
So, 30/42 + 15/9 = 50/21
In mixed form: 28/21

MathStep (Works offline)

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