Add 70/18 and 80/21
1st number: 3 16/18, 2nd number: 3 17/21
70/18 + 80/21 is 485/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
70/18 = 70 × 7/18 × 7 = 490/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
80/21 = 80 × 6/21 × 6 = 480/126 - Add the two like fractions:
490/126 + 480/126 = 490 + 480/126 = 970/126 - 970/126 simplified gives 485/63
- So, 70/18 + 80/21 = 485/63
In mixed form: 744/63
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