Add 21/20 and 40/63, Solve 1 1/20 + 40/63 as a fraction

Add 21/20 and 40/63

1^st number: 1 1/20, 2^nd number: 40/63

21/20 + 40/63 is 2123/1260.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 63 is 1260

Next, find the equivalent fraction of both fractional numbers with denominator 1260
For the 1st fraction, since 20 × 63 = 1260,
21/20 = 21 × 63/20 × 63 = 1323/1260
Likewise, for the 2nd fraction, since 63 × 20 = 1260,
40/63 = 40 × 20/63 × 20 = 800/1260
Add the two like fractions:
1323/1260 + 800/1260 = 1323 + 800/1260 = 2123/1260
So, 21/20 + 40/63 = 2123/1260
In mixed form: 1863/1260

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