Add 90/72 and 15/40
1st number: 1 18/72, 2nd number: 15/40
90/72 + 15/40 is 13/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 40 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 40 × 9 = 360,
15/40 = 15 × 9/40 × 9 = 135/360 - Add the two like fractions:
450/360 + 135/360 = 450 + 135/360 = 585/360 - 585/360 simplified gives 13/8
- So, 90/72 + 15/40 = 13/8
In mixed form: 15/8
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