Add 72/28 and 30/90
1st number: 2 16/28, 2nd number: 30/90
72/28 + 30/90 is 61/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 28 × 45 = 1260,
72/28 = 72 × 45/28 × 45 = 3240/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
30/90 = 30 × 14/90 × 14 = 420/1260 - Add the two like fractions:
3240/1260 + 420/1260 = 3240 + 420/1260 = 3660/1260 - 3660/1260 simplified gives 61/21
- So, 72/28 + 30/90 = 61/21
In mixed form: 219/21
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