Add 21/80 and 54/70
21/80 + 54/70 is 579/560.
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,
21/80 = 21 × 7/80 × 7 = 147/560 - Likewise, for the 2nd fraction, since 70 × 8 = 560,
54/70 = 54 × 8/70 × 8 = 432/560 - Add the two like fractions:
147/560 + 432/560 = 147 + 432/560 = 579/560 - So, 21/80 + 54/70 = 579/560
In mixed form: 119/560
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