Add 9/45 and 42/21
1st number: 9/45, 2nd number: 2 0/21
9/45 + 42/21 is 11/5.
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,
9/45 = 9 × 7/45 × 7 = 63/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
42/21 = 42 × 15/21 × 15 = 630/315 - Add the two like fractions:
63/315 + 630/315 = 63 + 630/315 = 693/315 - 693/315 simplified gives 11/5
- So, 9/45 + 42/21 = 11/5
In mixed form: 21/5
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