Add 15/30 and 70/90
15/30 + 70/90 is 23/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
15/30 = 15 × 3/30 × 3 = 45/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
70/90 = 70 × 1/90 × 1 = 70/90 - Add the two like fractions:
45/90 + 70/90 = 45 + 70/90 = 115/90 - 115/90 simplified gives 23/18
- So, 15/30 + 70/90 = 23/18
In mixed form: 15/18
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