Add 42/84 and 72/90
42/84 + 72/90 is 13/10.
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,
42/84 = 42 × 15/84 × 15 = 630/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
72/90 = 72 × 14/90 × 14 = 1008/1260 - Add the two like fractions:
630/1260 + 1008/1260 = 630 + 1008/1260 = 1638/1260 - 1638/1260 simplified gives 13/10
- So, 42/84 + 72/90 = 13/10
In mixed form: 13/10
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