Add 21/30 and 18/90
21/30 + 18/90 is 9/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
18/90 = 18 × 1/90 × 1 = 18/90 - Add the two like fractions:
63/90 + 18/90 = 63 + 18/90 = 81/90 - 81/90 simplified gives 9/10
- So, 21/30 + 18/90 = 9/10
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