Add 21/70 and 63/80
21/70 + 63/80 is 87/80.
Steps for adding fractions
- 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,
21/70 = 21 × 8/70 × 8 = 168/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
63/80 = 63 × 7/80 × 7 = 441/560 - Add the two like fractions:
168/560 + 441/560 = 168 + 441/560 = 609/560 - 609/560 simplified gives 87/80
- So, 21/70 + 63/80 = 87/80
In mixed form: 17/80
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