Add 72/90 and 20/56
72/90 + 20/56 is 81/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 56 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 90 × 28 = 2520,
72/90 = 72 × 28/90 × 28 = 2016/2520 - Likewise, for the 2nd fraction, since 56 × 45 = 2520,
20/56 = 20 × 45/56 × 45 = 900/2520 - Add the two like fractions:
2016/2520 + 900/2520 = 2016 + 900/2520 = 2916/2520 - 2916/2520 simplified gives 81/70
- So, 72/90 + 20/56 = 81/70
In mixed form: 111/70
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