Add 15/56 and 21/90
15/56 + 21/90 is 421/840.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 90 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 56 × 45 = 2520,
15/56 = 15 × 45/56 × 45 = 675/2520 - Likewise, for the 2nd fraction, since 90 × 28 = 2520,
21/90 = 21 × 28/90 × 28 = 588/2520 - Add the two like fractions:
675/2520 + 588/2520 = 675 + 588/2520 = 1263/2520 - 1263/2520 simplified gives 421/840
- So, 15/56 + 21/90 = 421/840
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