Add 15/28 and 21/40
15/28 + 21/40 is 297/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 28 × 10 = 280,
15/28 = 15 × 10/28 × 10 = 150/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Add the two like fractions:
150/280 + 147/280 = 150 + 147/280 = 297/280 - So, 15/28 + 21/40 = 297/280
In mixed form: 117/280
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