Add 21/14 and 15/40
1st number: 1 7/14, 2nd number: 15/40
21/14 + 15/40 is 15/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 14 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 14 × 20 = 280,
21/14 = 21 × 20/14 × 20 = 420/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
15/40 = 15 × 7/40 × 7 = 105/280 - Add the two like fractions:
420/280 + 105/280 = 420 + 105/280 = 525/280 - 525/280 simplified gives 15/8
- So, 21/14 + 15/40 = 15/8
In mixed form: 17/8
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