Add 20/72 and 70/90
20/72 + 70/90 is 19/18.
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,
20/72 = 20 × 5/72 × 5 = 100/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
70/90 = 70 × 4/90 × 4 = 280/360 - Add the two like fractions:
100/360 + 280/360 = 100 + 280/360 = 380/360 - 380/360 simplified gives 19/18
- So, 20/72 + 70/90 = 19/18
In mixed form: 11/18
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