Add 20/40 and 70/90
20/40 + 70/90 is 23/18.
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,
70/90 = 70 × 4/90 × 4 = 280/360 - Add the two like fractions:
180/360 + 280/360 = 180 + 280/360 = 460/360 - 460/360 simplified gives 23/18
- So, 20/40 + 70/90 = 23/18
In mixed form: 15/18
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