Add 15/20 and 10/90
15/20 + 10/90 is 31/36.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
15/20 = 15 × 9/20 × 9 = 135/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
10/90 = 10 × 2/90 × 2 = 20/180 - Add the two like fractions:
135/180 + 20/180 = 135 + 20/180 = 155/180 - 155/180 simplified gives 31/36
- So, 15/20 + 10/90 = 31/36
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