Add 72/80 and 70/42
1st number: 72/80, 2nd number: 1 28/42
72/80 + 70/42 is 77/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 42 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
72/80 = 72 × 21/80 × 21 = 1512/1680 - Likewise, for the 2nd fraction, since 42 × 40 = 1680,
70/42 = 70 × 40/42 × 40 = 2800/1680 - Add the two like fractions:
1512/1680 + 2800/1680 = 1512 + 2800/1680 = 4312/1680 - 4312/1680 simplified gives 77/30
- So, 72/80 + 70/42 = 77/30
In mixed form: 217/30
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