Add 15/20 and 70/84
15/20 + 70/84 is 19/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
15/20 = 15 × 21/20 × 21 = 315/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
70/84 = 70 × 5/84 × 5 = 350/420 - Add the two like fractions:
315/420 + 350/420 = 315 + 350/420 = 665/420 - 665/420 simplified gives 19/12
- So, 15/20 + 70/84 = 19/12
In mixed form: 17/12
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