Add 80/21 and 40/9
1st number: 3 17/21, 2nd number: 4 4/9
80/21 + 40/9 is 520/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
80/21 = 80 × 3/21 × 3 = 240/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
40/9 = 40 × 7/9 × 7 = 280/63 - Add the two like fractions:
240/63 + 280/63 = 240 + 280/63 = 520/63 - So, 80/21 + 40/9 = 520/63
In mixed form: 816/63
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