Add 90/3 and 21/40, Solve 30 0/3 + 21/40 as a fraction

Add 90/3 and 21/40

1^st number: 30 0/3, 2^nd number: 21/40

90/3 + 21/40 is 1221/40.

Find the least common denominator or LCM of the two denominators:
LCM of 3 and 40 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 3 × 40 = 120,
90/3 = 90 × 40/3 × 40 = 3600/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120
Add the two like fractions:
3600/120 + 63/120 = 3600 + 63/120 = 3663/120
3663/120 simplified gives 1221/40
So, 90/3 + 21/40 = 1221/40
In mixed form: 3021/40

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