Add 21/90 and 20/36
21/90 + 20/36 is 71/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 36 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
21/90 = 21 × 2/90 × 2 = 42/180 - Likewise, for the 2nd fraction, since 36 × 5 = 180,
20/36 = 20 × 5/36 × 5 = 100/180 - Add the two like fractions:
42/180 + 100/180 = 42 + 100/180 = 142/180 - 142/180 simplified gives 71/90
- So, 21/90 + 20/36 = 71/90
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