Add 18/21 and 42/80
18/21 + 42/80 is 387/280.
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,
18/21 = 18 × 80/21 × 80 = 1440/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
42/80 = 42 × 21/80 × 21 = 882/1680 - Add the two like fractions:
1440/1680 + 882/1680 = 1440 + 882/1680 = 2322/1680 - 2322/1680 simplified gives 387/280
- So, 18/21 + 42/80 = 387/280
In mixed form: 1107/280
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