Add 80/8 and 90/21
1st number: 10 0/8, 2nd number: 4 6/21
80/8 + 90/21 is 100/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
80/8 = 80 × 21/8 × 21 = 1680/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
90/21 = 90 × 8/21 × 8 = 720/168 - Add the two like fractions:
1680/168 + 720/168 = 1680 + 720/168 = 2400/168 - 2400/168 simplified gives 100/7
- So, 80/8 + 90/21 = 100/7
In mixed form: 142/7
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