Add 72/14 and 90/21
1st number: 5 2/14, 2nd number: 4 6/21
72/14 + 90/21 is 66/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 14 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 14 × 3 = 42,
72/14 = 72 × 3/14 × 3 = 216/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
90/21 = 90 × 2/21 × 2 = 180/42 - Add the two like fractions:
216/42 + 180/42 = 216 + 180/42 = 396/42 - 396/42 simplified gives 66/7
- So, 72/14 + 90/21 = 66/7
In mixed form: 93/7
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