Add 25/28 and 42/90
25/28 + 42/90 is 571/420.
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,
25/28 = 25 × 45/28 × 45 = 1125/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
42/90 = 42 × 14/90 × 14 = 588/1260 - Add the two like fractions:
1125/1260 + 588/1260 = 1125 + 588/1260 = 1713/1260 - 1713/1260 simplified gives 571/420
- So, 25/28 + 42/90 = 571/420
In mixed form: 1151/420
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