Add 30/80 and 18/21
30/80 + 18/21 is 69/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
30/80 = 30 × 21/80 × 21 = 630/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
18/21 = 18 × 80/21 × 80 = 1440/1680 - Add the two like fractions:
630/1680 + 1440/1680 = 630 + 1440/1680 = 2070/1680 - 2070/1680 simplified gives 69/56
- So, 30/80 + 18/21 = 69/56
In mixed form: 113/56
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