Add 72/84 and 42/90
72/84 + 42/90 is 139/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
72/84 = 72 × 15/84 × 15 = 1080/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
42/90 = 42 × 14/90 × 14 = 588/1260 - Add the two like fractions:
1080/1260 + 588/1260 = 1080 + 588/1260 = 1668/1260 - 1668/1260 simplified gives 139/105
- So, 72/84 + 42/90 = 139/105
In mixed form: 134/105
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