Add 15/21 and 70/80
15/21 + 70/80 is 89/56.
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,
70/80 = 70 × 21/80 × 21 = 1470/1680 - Add the two like fractions:
1200/1680 + 1470/1680 = 1200 + 1470/1680 = 2670/1680 - 2670/1680 simplified gives 89/56
- So, 15/21 + 70/80 = 89/56
In mixed form: 133/56
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