Add 40/84 and 80/90
40/84 + 80/90 is 86/63.
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,
40/84 = 40 × 15/84 × 15 = 600/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
80/90 = 80 × 14/90 × 14 = 1120/1260 - Add the two like fractions:
600/1260 + 1120/1260 = 600 + 1120/1260 = 1720/1260 - 1720/1260 simplified gives 86/63
- So, 40/84 + 80/90 = 86/63
In mixed form: 123/63
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