Add 21/5 and 90/8
1st number: 4 1/5, 2nd number: 11 2/8
21/5 + 90/8 is 309/20.
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,
90/8 = 90 × 5/8 × 5 = 450/40 - Add the two like fractions:
168/40 + 450/40 = 168 + 450/40 = 618/40 - 618/40 simplified gives 309/20
- So, 21/5 + 90/8 = 309/20
In mixed form: 159/20
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