Add 18/21 and 63/80
18/21 + 63/80 is 921/560.
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,
18/21 = 18 × 80/21 × 80 = 1440/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
63/80 = 63 × 21/80 × 21 = 1323/1680 - Add the two like fractions:
1440/1680 + 1323/1680 = 1440 + 1323/1680 = 2763/1680 - 2763/1680 simplified gives 921/560
- So, 18/21 + 63/80 = 921/560
In mixed form: 1361/560
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