Add 21/7 and 42/8
1st number: 3 0/7, 2nd number: 5 2/8
21/7 + 42/8 is 33/4.
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,
42/8 = 42 × 7/8 × 7 = 294/56 - Add the two like fractions:
168/56 + 294/56 = 168 + 294/56 = 462/56 - 462/56 simplified gives 33/4
- So, 21/7 + 42/8 = 33/4
In mixed form: 81/4
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