Add 10/45 and 42/21
1st number: 10/45, 2nd number: 2 0/21
10/45 + 42/21 is 20/9.
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,
10/45 = 10 × 7/45 × 7 = 70/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
42/21 = 42 × 15/21 × 15 = 630/315 - Add the two like fractions:
70/315 + 630/315 = 70 + 630/315 = 700/315 - 700/315 simplified gives 20/9
- So, 10/45 + 42/21 = 20/9
In mixed form: 22/9
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