Add 70/60 and 18/21
1st number: 1 10/60, 2nd number: 18/21
70/60 + 18/21 is 85/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
70/60 = 70 × 7/60 × 7 = 490/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
18/21 = 18 × 20/21 × 20 = 360/420 - Add the two like fractions:
490/420 + 360/420 = 490 + 360/420 = 850/420 - 850/420 simplified gives 85/42
- So, 70/60 + 18/21 = 85/42
In mixed form: 21/42
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