Add 21/8 and 42/7
1st number: 2 5/8, 2nd number: 6 0/7
21/8 + 42/7 is 69/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 7 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 8 × 7 = 56,
21/8 = 21 × 7/8 × 7 = 147/56 - Likewise, for the 2nd fraction, since 7 × 8 = 56,
42/7 = 42 × 8/7 × 8 = 336/56 - Add the two like fractions:
147/56 + 336/56 = 147 + 336/56 = 483/56 - 483/56 simplified gives 69/8
- So, 21/8 + 42/7 = 69/8
In mixed form: 85/8
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