Add 21/40 and 15/9, Solve 21/40 + 1 6/9 as a fraction

Add 21/40 and 15/9

1^st number: 21/40, 2^nd number: 1 6/9

21/40 + 15/9 is 263/120.

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,
21/40 = 21 × 9/40 × 9 = 189/360
Likewise, for the 2nd fraction, since 9 × 40 = 360,
15/9 = 15 × 40/9 × 40 = 600/360
Add the two like fractions:
189/360 + 600/360 = 189 + 600/360 = 789/360
789/360 simplified gives 263/120
So, 21/40 + 15/9 = 263/120
In mixed form: 223/120

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