Add 21/84 and 70/90
21/84 + 70/90 is 37/36.
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,
21/84 = 21 × 15/84 × 15 = 315/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
70/90 = 70 × 14/90 × 14 = 980/1260 - Add the two like fractions:
315/1260 + 980/1260 = 315 + 980/1260 = 1295/1260 - 1295/1260 simplified gives 37/36
- So, 21/84 + 70/90 = 37/36
In mixed form: 11/36
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