Add 3/21 and 90/45
1st number: 3/21, 2nd number: 2 0/45
3/21 + 90/45 is 15/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
3/21 = 3 × 15/21 × 15 = 45/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
90/45 = 90 × 7/45 × 7 = 630/315 - Add the two like fractions:
45/315 + 630/315 = 45 + 630/315 = 675/315 - 675/315 simplified gives 15/7
- So, 3/21 + 90/45 = 15/7
In mixed form: 21/7
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