Add 21/7 and 20/8
1st number: 3 0/7, 2nd number: 2 4/8
21/7 + 20/8 is 11/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 8 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 7 × 8 = 56,
21/7 = 21 × 8/7 × 8 = 168/56 - Likewise, for the 2nd fraction, since 8 × 7 = 56,
20/8 = 20 × 7/8 × 7 = 140/56 - Add the two like fractions:
168/56 + 140/56 = 168 + 140/56 = 308/56 - 308/56 simplified gives 11/2
- So, 21/7 + 20/8 = 11/2
In mixed form: 51/2
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