Add 42/45 and 75/21
1st number: 42/45, 2nd number: 3 12/21
42/45 + 75/21 is 473/105.
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,
42/45 = 42 × 7/45 × 7 = 294/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
75/21 = 75 × 15/21 × 15 = 1125/315 - Add the two like fractions:
294/315 + 1125/315 = 294 + 1125/315 = 1419/315 - 1419/315 simplified gives 473/105
- So, 42/45 + 75/21 = 473/105
In mixed form: 453/105
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