Add 80/21 and 18/42
1st number: 3 17/21, 2nd number: 18/42
80/21 + 18/42 is 89/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
80/21 = 80 × 2/21 × 2 = 160/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
18/42 = 18 × 1/42 × 1 = 18/42 - Add the two like fractions:
160/42 + 18/42 = 160 + 18/42 = 178/42 - 178/42 simplified gives 89/21
- So, 80/21 + 18/42 = 89/21
In mixed form: 45/21
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