Add 90/6 and 72/21
1st number: 15 0/6, 2nd number: 3 9/21
90/6 + 72/21 is 129/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 6 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 6 × 7 = 42,
90/6 = 90 × 7/6 × 7 = 630/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
72/21 = 72 × 2/21 × 2 = 144/42 - Add the two like fractions:
630/42 + 144/42 = 630 + 144/42 = 774/42 - 774/42 simplified gives 129/7
- So, 90/6 + 72/21 = 129/7
In mixed form: 183/7
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