Add 90/72 and 20/15
1st number: 1 18/72, 2nd number: 1 5/15
90/72 + 20/15 is 31/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 15 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360 - Likewise, for the 2nd fraction, since 15 × 24 = 360,
20/15 = 20 × 24/15 × 24 = 480/360 - Add the two like fractions:
450/360 + 480/360 = 450 + 480/360 = 930/360 - 930/360 simplified gives 31/12
- So, 90/72 + 20/15 = 31/12
In mixed form: 27/12
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