Add 70/42 and 81/80
1st number: 1 28/42, 2nd number: 1 1/80
70/42 + 81/80 is 643/240.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 42 × 40 = 1680,
70/42 = 70 × 40/42 × 40 = 2800/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
81/80 = 81 × 21/80 × 21 = 1701/1680 - Add the two like fractions:
2800/1680 + 1701/1680 = 2800 + 1701/1680 = 4501/1680 - 4501/1680 simplified gives 643/240
- So, 70/42 + 81/80 = 643/240
In mixed form: 2163/240
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