Add 42/84 and 72/20
1st number: 42/84, 2nd number: 3 12/20
42/84 + 72/20 is 41/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
42/84 = 42 × 5/84 × 5 = 210/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420 - Add the two like fractions:
210/420 + 1512/420 = 210 + 1512/420 = 1722/420 - 1722/420 simplified gives 41/10
- So, 42/84 + 72/20 = 41/10
In mixed form: 41/10
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