Add 70/21 and 40/28
1st number: 3 7/21, 2nd number: 1 12/28
70/21 + 40/28 is 100/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
70/21 = 70 × 4/21 × 4 = 280/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
40/28 = 40 × 3/28 × 3 = 120/84 - Add the two like fractions:
280/84 + 120/84 = 280 + 120/84 = 400/84 - 400/84 simplified gives 100/21
- So, 70/21 + 40/28 = 100/21
In mixed form: 416/21
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