Add 18/84 and 72/90
18/84 + 72/90 is 71/70.
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,
18/84 = 18 × 15/84 × 15 = 270/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
72/90 = 72 × 14/90 × 14 = 1008/1260 - Add the two like fractions:
270/1260 + 1008/1260 = 270 + 1008/1260 = 1278/1260 - 1278/1260 simplified gives 71/70
- So, 18/84 + 72/90 = 71/70
In mixed form: 11/70
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