Add 15/28 and 42/90
15/28 + 42/90 is 421/420.
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,
42/90 = 42 × 14/90 × 14 = 588/1260 - Add the two like fractions:
675/1260 + 588/1260 = 675 + 588/1260 = 1263/1260 - 1263/1260 simplified gives 421/420
- So, 15/28 + 42/90 = 421/420
In mixed form: 11/420
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