Add 18/72 and 20/90
18/72 + 20/90 is 17/36.
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,
18/72 = 18 × 5/72 × 5 = 90/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
20/90 = 20 × 4/90 × 4 = 80/360 - Add the two like fractions:
90/360 + 80/360 = 90 + 80/360 = 170/360 - 170/360 simplified gives 17/36
- So, 18/72 + 20/90 = 17/36
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