Add 90/72 and 80/20
1st number: 1 18/72, 2nd number: 4 0/20
90/72 + 80/20 is 21/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 20 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 20 × 18 = 360,
80/20 = 80 × 18/20 × 18 = 1440/360 - Add the two like fractions:
450/360 + 1440/360 = 450 + 1440/360 = 1890/360 - 1890/360 simplified gives 21/4
- So, 90/72 + 80/20 = 21/4
In mixed form: 51/4
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