Add 21/30 and 25/21, Solve 21/30 + 1 4/21 as a fraction

Add 21/30 and 25/21

1^st number: 21/30, 2^nd number: 1 4/21

21/30 + 25/21 is 397/210.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 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 21 × 10 = 210,
25/21 = 25 × 10/21 × 10 = 250/210
Add the two like fractions:
147/210 + 250/210 = 147 + 250/210 = 397/210
So, 21/30 + 25/21 = 397/210
In mixed form: 1187/210

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