Add 15/21 and 54/80
15/21 + 54/80 is 389/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
15/21 = 15 × 80/21 × 80 = 1200/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
54/80 = 54 × 21/80 × 21 = 1134/1680 - Add the two like fractions:
1200/1680 + 1134/1680 = 1200 + 1134/1680 = 2334/1680 - 2334/1680 simplified gives 389/280
- So, 15/21 + 54/80 = 389/280
In mixed form: 1109/280
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