Add 18/45 and 20/21
18/45 + 20/21 is 142/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
18/45 = 18 × 7/45 × 7 = 126/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
20/21 = 20 × 15/21 × 15 = 300/315 - Add the two like fractions:
126/315 + 300/315 = 126 + 300/315 = 426/315 - 426/315 simplified gives 142/105
- So, 18/45 + 20/21 = 142/105
In mixed form: 137/105
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