Add 15/28 and 21/90
15/28 + 21/90 is 323/420.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 28 × 45 = 1260,
15/28 = 15 × 45/28 × 45 = 675/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
21/90 = 21 × 14/90 × 14 = 294/1260 - Add the two like fractions:
675/1260 + 294/1260 = 675 + 294/1260 = 969/1260 - 969/1260 simplified gives 323/420
- So, 15/28 + 21/90 = 323/420
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