Add 21/15 and 42/8
1st number: 1 6/15, 2nd number: 5 2/8
21/15 + 42/8 is 133/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 8 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 15 × 8 = 120,
21/15 = 21 × 8/15 × 8 = 168/120 - Likewise, for the 2nd fraction, since 8 × 15 = 120,
42/8 = 42 × 15/8 × 15 = 630/120 - Add the two like fractions:
168/120 + 630/120 = 168 + 630/120 = 798/120 - 798/120 simplified gives 133/20
- So, 21/15 + 42/8 = 133/20
In mixed form: 613/20
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