Add 42/8 and 90/21
1st number: 5 2/8, 2nd number: 4 6/21
42/8 + 90/21 is 267/28.
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,
42/8 = 42 × 21/8 × 21 = 882/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
90/21 = 90 × 8/21 × 8 = 720/168 - Add the two like fractions:
882/168 + 720/168 = 882 + 720/168 = 1602/168 - 1602/168 simplified gives 267/28
- So, 42/8 + 90/21 = 267/28
In mixed form: 915/28
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