Add 70/84 and 21/90
70/84 + 21/90 is 16/15.
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,
70/84 = 70 × 15/84 × 15 = 1050/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
21/90 = 21 × 14/90 × 14 = 294/1260 - Add the two like fractions:
1050/1260 + 294/1260 = 1050 + 294/1260 = 1344/1260 - 1344/1260 simplified gives 16/15
- So, 70/84 + 21/90 = 16/15
In mixed form: 11/15
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