Add 21/56 and 80/90
21/56 + 80/90 is 91/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 90 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 56 × 45 = 2520,
21/56 = 21 × 45/56 × 45 = 945/2520 - Likewise, for the 2nd fraction, since 90 × 28 = 2520,
80/90 = 80 × 28/90 × 28 = 2240/2520 - Add the two like fractions:
945/2520 + 2240/2520 = 945 + 2240/2520 = 3185/2520 - 3185/2520 simplified gives 91/72
- So, 21/56 + 80/90 = 91/72
In mixed form: 119/72
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