Add 18/20 and 70/42
1st number: 18/20, 2nd number: 1 28/42
18/20 + 70/42 is 77/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
18/20 = 18 × 21/20 × 21 = 378/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
70/42 = 70 × 10/42 × 10 = 700/420 - Add the two like fractions:
378/420 + 700/420 = 378 + 700/420 = 1078/420 - 1078/420 simplified gives 77/30
- So, 18/20 + 70/42 = 77/30
In mixed form: 217/30
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