Add 3/45 and 42/21
1st number: 3/45, 2nd number: 2 0/21
3/45 + 42/21 is 31/15.
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,
3/45 = 3 × 7/45 × 7 = 21/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
42/21 = 42 × 15/21 × 15 = 630/315 - Add the two like fractions:
21/315 + 630/315 = 21 + 630/315 = 651/315 - 651/315 simplified gives 31/15
- So, 3/45 + 42/21 = 31/15
In mixed form: 21/15
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