Add 9/4 and 90/72, Solve 2 1/4 + 1 18/72 as a fraction

Add 9/4 and 90/72

1^st number: 2 1/4, 2^nd number: 1 18/72

9/4 + 90/72 is 7/2.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 72 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 4 × 18 = 72,
9/4 = 9 × 18/4 × 18 = 162/72
Likewise, for the 2nd fraction, since 72 × 1 = 72,
90/72 = 90 × 1/72 × 1 = 90/72
Add the two like fractions:
162/72 + 90/72 = 162 + 90/72 = 252/72
252/72 simplified gives 7/2
So, 9/4 + 90/72 = 7/2
In mixed form: 31/2

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