Add 30/80 and 70/21
1st number: 30/80, 2nd number: 3 7/21
30/80 + 70/21 is 89/24.
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,
70/21 = 70 × 80/21 × 80 = 5600/1680 - Add the two like fractions:
630/1680 + 5600/1680 = 630 + 5600/1680 = 6230/1680 - 6230/1680 simplified gives 89/24
- So, 30/80 + 70/21 = 89/24
In mixed form: 317/24
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