Add 18/45 and 42/90
18/45 + 42/90 is 13/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
18/45 = 18 × 2/45 × 2 = 36/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
42/90 = 42 × 1/90 × 1 = 42/90 - Add the two like fractions:
36/90 + 42/90 = 36 + 42/90 = 78/90 - 78/90 simplified gives 13/15
- So, 18/45 + 42/90 = 13/15
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