Add 18/21 and 42/45
18/21 + 42/45 is 188/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
18/21 = 18 × 15/21 × 15 = 270/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
42/45 = 42 × 7/45 × 7 = 294/315 - Add the two like fractions:
270/315 + 294/315 = 270 + 294/315 = 564/315 - 564/315 simplified gives 188/105
- So, 18/21 + 42/45 = 188/105
In mixed form: 183/105
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