Add 72/80 and 20/28
72/80 + 20/28 is 113/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 28 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
72/80 = 72 × 7/80 × 7 = 504/560 - Likewise, for the 2nd fraction, since 28 × 20 = 560,
20/28 = 20 × 20/28 × 20 = 400/560 - Add the two like fractions:
504/560 + 400/560 = 504 + 400/560 = 904/560 - 904/560 simplified gives 113/70
- So, 72/80 + 20/28 = 113/70
In mixed form: 143/70
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