Add 21/45 and 56/80
21/45 + 56/80 is 7/6.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 45 × 16 = 720,
21/45 = 21 × 16/45 × 16 = 336/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
56/80 = 56 × 9/80 × 9 = 504/720 - Add the two like fractions:
336/720 + 504/720 = 336 + 504/720 = 840/720 - 840/720 simplified gives 7/6
- So, 21/45 + 56/80 = 7/6
In mixed form: 11/6
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