Add 20/40 and 72/90
20/40 + 72/90 is 13/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
20/40 = 20 × 9/40 × 9 = 180/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
72/90 = 72 × 4/90 × 4 = 288/360 - Add the two like fractions:
180/360 + 288/360 = 180 + 288/360 = 468/360 - 468/360 simplified gives 13/10
- So, 20/40 + 72/90 = 13/10
In mixed form: 13/10
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