Add 20/90 and 70/84
20/90 + 70/84 is 19/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 84 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 90 × 14 = 1260,
20/90 = 20 × 14/90 × 14 = 280/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
70/84 = 70 × 15/84 × 15 = 1050/1260 - Add the two like fractions:
280/1260 + 1050/1260 = 280 + 1050/1260 = 1330/1260 - 1330/1260 simplified gives 19/18
- So, 20/90 + 70/84 = 19/18
In mixed form: 11/18
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