Add 18/20 and 40/42
18/20 + 40/42 is 389/210.
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,
40/42 = 40 × 10/42 × 10 = 400/420 - Add the two like fractions:
378/420 + 400/420 = 378 + 400/420 = 778/420 - 778/420 simplified gives 389/210
- So, 18/20 + 40/42 = 389/210
In mixed form: 1179/210
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