Add 21/36 and 90/40, Solve 21/36 + 2 10/40 as a fraction

Add 21/36 and 90/40

1^st number: 21/36, 2^nd number: 2 10/40

21/36 + 90/40 is 17/6.

Find the least common denominator or LCM of the two denominators:
LCM of 36 and 40 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 36 × 10 = 360,
21/36 = 21 × 10/36 × 10 = 210/360
Likewise, for the 2nd fraction, since 40 × 9 = 360,
90/40 = 90 × 9/40 × 9 = 810/360
Add the two like fractions:
210/360 + 810/360 = 210 + 810/360 = 1020/360
1020/360 simplified gives 17/6
So, 21/36 + 90/40 = 17/6
In mixed form: 25/6

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