Add 80/70 and 21/80, Solve 1 10/70 + 21/80 as a fraction

Add 80/70 and 21/80

1^st number: 1 10/70, 2^nd number: 21/80

80/70 + 21/80 is 787/560.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 80 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 70 × 8 = 560,
80/70 = 80 × 8/70 × 8 = 640/560
Likewise, for the 2nd fraction, since 80 × 7 = 560,
21/80 = 21 × 7/80 × 7 = 147/560
Add the two like fractions:
640/560 + 147/560 = 640 + 147/560 = 787/560
So, 80/70 + 21/80 = 787/560
In mixed form: 1227/560

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