Add 12/28 and 80/90
12/28 + 80/90 is 83/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 28 × 45 = 1260,
12/28 = 12 × 45/28 × 45 = 540/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
80/90 = 80 × 14/90 × 14 = 1120/1260 - Add the two like fractions:
540/1260 + 1120/1260 = 540 + 1120/1260 = 1660/1260 - 1660/1260 simplified gives 83/63
- So, 12/28 + 80/90 = 83/63
In mixed form: 120/63
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