Add 75/15 and 90/21
1st number: 5 0/15, 2nd number: 4 6/21
75/15 + 90/21 is 65/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
75/15 = 75 × 7/15 × 7 = 525/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
90/21 = 90 × 5/21 × 5 = 450/105 - Add the two like fractions:
525/105 + 450/105 = 525 + 450/105 = 975/105 - 975/105 simplified gives 65/7
- So, 75/15 + 90/21 = 65/7
In mixed form: 92/7
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