Add 15/5 and 90/21
1st number: 3 0/5, 2nd number: 4 6/21
15/5 + 90/21 is 51/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
15/5 = 15 × 21/5 × 21 = 315/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
90/21 = 90 × 5/21 × 5 = 450/105 - Add the two like fractions:
315/105 + 450/105 = 315 + 450/105 = 765/105 - 765/105 simplified gives 51/7
- So, 15/5 + 90/21 = 51/7
In mixed form: 72/7
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