Add 21/75 and 18/90
21/75 + 18/90 is 12/25.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 90 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 75 × 6 = 450,
21/75 = 21 × 6/75 × 6 = 126/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
18/90 = 18 × 5/90 × 5 = 90/450 - Add the two like fractions:
126/450 + 90/450 = 126 + 90/450 = 216/450 - 216/450 simplified gives 12/25
- So, 21/75 + 18/90 = 12/25
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