Add 20/84 and 80/90
20/84 + 80/90 is 71/63.
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,
20/84 = 20 × 15/84 × 15 = 300/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
80/90 = 80 × 14/90 × 14 = 1120/1260 - Add the two like fractions:
300/1260 + 1120/1260 = 300 + 1120/1260 = 1420/1260 - 1420/1260 simplified gives 71/63
- So, 20/84 + 80/90 = 71/63
In mixed form: 18/63
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