Add 21/30 and 40/63, Solve 21/30 + 40/63 as a fraction

Add 21/30 and 40/63

21/30 + 40/63 is 841/630.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 63 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 30 × 21 = 630,
21/30 = 21 × 21/30 × 21 = 441/630
Likewise, for the 2nd fraction, since 63 × 10 = 630,
40/63 = 40 × 10/63 × 10 = 400/630
Add the two like fractions:
441/630 + 400/630 = 441 + 400/630 = 841/630
So, 21/30 + 40/63 = 841/630
In mixed form: 1211/630

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