Add 72/20 and 90/84
1st number: 3 12/20, 2nd number: 1 6/84
72/20 + 90/84 is 327/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
90/84 = 90 × 5/84 × 5 = 450/420 - Add the two like fractions:
1512/420 + 450/420 = 1512 + 450/420 = 1962/420 - 1962/420 simplified gives 327/70
- So, 72/20 + 90/84 = 327/70
In mixed form: 447/70
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