Add 15/8 and 42/21
1st number: 1 7/8, 2nd number: 2 0/21
15/8 + 42/21 is 31/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
15/8 = 15 × 21/8 × 21 = 315/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
42/21 = 42 × 8/21 × 8 = 336/168 - Add the two like fractions:
315/168 + 336/168 = 315 + 336/168 = 651/168 - 651/168 simplified gives 31/8
- So, 15/8 + 42/21 = 31/8
In mixed form: 37/8
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