Add 70/42 and 21/80
1st number: 1 28/42, 2nd number: 21/80
70/42 + 21/80 is 463/240.
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,
21/80 = 21 × 21/80 × 21 = 441/1680 - Add the two like fractions:
2800/1680 + 441/1680 = 2800 + 441/1680 = 3241/1680 - 3241/1680 simplified gives 463/240
- So, 70/42 + 21/80 = 463/240
In mixed form: 1223/240
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