Add 21/7 and 18/80
1st number: 3 0/7, 2nd number: 18/80
21/7 + 18/80 is 129/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 80 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 7 × 80 = 560,
21/7 = 21 × 80/7 × 80 = 1680/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
18/80 = 18 × 7/80 × 7 = 126/560 - Add the two like fractions:
1680/560 + 126/560 = 1680 + 126/560 = 1806/560 - 1806/560 simplified gives 129/40
- So, 21/7 + 18/80 = 129/40
In mixed form: 39/40
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