Add 15/80 and 21/70
15/80 + 21/70 is 39/80.
Steps for adding fractions
- 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,
15/80 = 15 × 7/80 × 7 = 105/560 - Likewise, for the 2nd fraction, since 70 × 8 = 560,
21/70 = 21 × 8/70 × 8 = 168/560 - Add the two like fractions:
105/560 + 168/560 = 105 + 168/560 = 273/560 - 273/560 simplified gives 39/80
- So, 15/80 + 21/70 = 39/80
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