Add 72/84 and 20/90
72/84 + 20/90 is 68/63.
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,
20/90 = 20 × 14/90 × 14 = 280/1260 - Add the two like fractions:
1080/1260 + 280/1260 = 1080 + 280/1260 = 1360/1260 - 1360/1260 simplified gives 68/63
- So, 72/84 + 20/90 = 68/63
In mixed form: 15/63
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