Add 21/35 and 15/8
1st number: 21/35, 2nd number: 1 7/8
21/35 + 15/8 is 99/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 8 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 35 × 8 = 280,
21/35 = 21 × 8/35 × 8 = 168/280 - Likewise, for the 2nd fraction, since 8 × 35 = 280,
15/8 = 15 × 35/8 × 35 = 525/280 - Add the two like fractions:
168/280 + 525/280 = 168 + 525/280 = 693/280 - 693/280 simplified gives 99/40
- So, 21/35 + 15/8 = 99/40
In mixed form: 219/40
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