Add 21/30 and 60/42, Solve 21/30 + 1 18/42 as a fraction

Add 21/30 and 60/42

1^st number: 21/30, 2^nd number: 1 18/42

21/30 + 60/42 is 149/70.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
60/42 = 60 × 5/42 × 5 = 300/210
Add the two like fractions:
147/210 + 300/210 = 147 + 300/210 = 447/210
447/210 simplified gives 149/70
So, 21/30 + 60/42 = 149/70
In mixed form: 29/70

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