Add 18/21 and 21/45
18/21 + 21/45 is 139/105.
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,
21/45 = 21 × 7/45 × 7 = 147/315 - Add the two like fractions:
270/315 + 147/315 = 270 + 147/315 = 417/315 - 417/315 simplified gives 139/105
- So, 18/21 + 21/45 = 139/105
In mixed form: 134/105
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