Add 18/30 and 21/40
18/30 + 21/40 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
18/30 = 18 × 4/30 × 4 = 72/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Add the two like fractions:
72/120 + 63/120 = 72 + 63/120 = 135/120 - 135/120 simplified gives 9/8
- So, 18/30 + 21/40 = 9/8
In mixed form: 11/8
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