Add 15/40 and 21/9, Solve 15/40 + 2 3/9 as a fraction

Add 15/40 and 21/9

1^st number: 15/40, 2^nd number: 2 3/9

15/40 + 21/9 is 65/24.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 9 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 40 × 9 = 360,
15/40 = 15 × 9/40 × 9 = 135/360
Likewise, for the 2nd fraction, since 9 × 40 = 360,
21/9 = 21 × 40/9 × 40 = 840/360
Add the two like fractions:
135/360 + 840/360 = 135 + 840/360 = 975/360
975/360 simplified gives 65/24
So, 15/40 + 21/9 = 65/24
In mixed form: 217/24

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