Add 21/45 and 12/7
1st number: 21/45, 2nd number: 1 5/7
21/45 + 12/7 is 229/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 7 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Likewise, for the 2nd fraction, since 7 × 45 = 315,
12/7 = 12 × 45/7 × 45 = 540/315 - Add the two like fractions:
147/315 + 540/315 = 147 + 540/315 = 687/315 - 687/315 simplified gives 229/105
- So, 21/45 + 12/7 = 229/105
In mixed form: 219/105
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