Add 15/21 and 56/80
15/21 + 56/80 is 99/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
15/21 = 15 × 80/21 × 80 = 1200/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
56/80 = 56 × 21/80 × 21 = 1176/1680 - Add the two like fractions:
1200/1680 + 1176/1680 = 1200 + 1176/1680 = 2376/1680 - 2376/1680 simplified gives 99/70
- So, 15/21 + 56/80 = 99/70
In mixed form: 129/70
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