Add 30/21 and 81/80
1st number: 1 9/21, 2nd number: 1 1/80
30/21 + 81/80 is 1367/560.
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,
30/21 = 30 × 80/21 × 80 = 2400/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
81/80 = 81 × 21/80 × 21 = 1701/1680 - Add the two like fractions:
2400/1680 + 1701/1680 = 2400 + 1701/1680 = 4101/1680 - 4101/1680 simplified gives 1367/560
- So, 30/21 + 81/80 = 1367/560
In mixed form: 2247/560
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