Add 21/5 and 28/8
1st number: 4 1/5, 2nd number: 3 4/8
21/5 + 28/8 is 77/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 5 × 8 = 40,
21/5 = 21 × 8/5 × 8 = 168/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
28/8 = 28 × 5/8 × 5 = 140/40 - Add the two like fractions:
168/40 + 140/40 = 168 + 140/40 = 308/40 - 308/40 simplified gives 77/10
- So, 21/5 + 28/8 = 77/10
In mixed form: 77/10
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