Add 20/25 and 81/90
20/25 + 81/90 is 17/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 90 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 25 × 18 = 450,
20/25 = 20 × 18/25 × 18 = 360/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
81/90 = 81 × 5/90 × 5 = 405/450 - Add the two like fractions:
360/450 + 405/450 = 360 + 405/450 = 765/450 - 765/450 simplified gives 17/10
- So, 20/25 + 81/90 = 17/10
In mixed form: 17/10
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