Add 21/80 and 10/7, Solve 21/80 + 1 3/7 as a fraction

Add 21/80 and 10/7

1^st number: 21/80, 2^nd number: 1 3/7

21/80 + 10/7 is 947/560.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 7 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 80 × 7 = 560,
21/80 = 21 × 7/80 × 7 = 147/560
Likewise, for the 2nd fraction, since 7 × 80 = 560,
10/7 = 10 × 80/7 × 80 = 800/560
Add the two like fractions:
147/560 + 800/560 = 147 + 800/560 = 947/560
So, 21/80 + 10/7 = 947/560
In mixed form: 1387/560

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