Add 21/80 and 75/70, Solve 21/80 + 1 5/70 as a fraction

Add 21/80 and 75/70

1^st number: 21/80, 2^nd number: 1 5/70

21/80 + 75/70 is 747/560.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 70 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 70 × 8 = 560,
75/70 = 75 × 8/70 × 8 = 600/560
Add the two like fractions:
147/560 + 600/560 = 147 + 600/560 = 747/560
So, 21/80 + 75/70 = 747/560
In mixed form: 1187/560

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