Add 90/45 and 9/21
1st number: 2 0/45, 2nd number: 9/21
90/45 + 9/21 is 17/7.
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,
90/45 = 90 × 7/45 × 7 = 630/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
9/21 = 9 × 15/21 × 15 = 135/315 - Add the two like fractions:
630/315 + 135/315 = 630 + 135/315 = 765/315 - 765/315 simplified gives 17/7
- So, 90/45 + 9/21 = 17/7
In mixed form: 23/7
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