Add 15/72 and 20/90
15/72 + 20/90 is 31/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
15/72 = 15 × 5/72 × 5 = 75/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
20/90 = 20 × 4/90 × 4 = 80/360 - Add the two like fractions:
75/360 + 80/360 = 75 + 80/360 = 155/360 - 155/360 simplified gives 31/72
- So, 15/72 + 20/90 = 31/72
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