Add 81/21 and 70/60
1st number: 3 18/21, 2nd number: 1 10/60
81/21 + 70/60 is 211/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 60 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
81/21 = 81 × 20/21 × 20 = 1620/420 - Likewise, for the 2nd fraction, since 60 × 7 = 420,
70/60 = 70 × 7/60 × 7 = 490/420 - Add the two like fractions:
1620/420 + 490/420 = 1620 + 490/420 = 2110/420 - 2110/420 simplified gives 211/42
- So, 81/21 + 70/60 = 211/42
In mixed form: 51/42
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