Add 42/72 and 15/9, Solve 42/72 + 1 6/9 as a fraction

Add 42/72 and 15/9

1^st number: 42/72, 2^nd number: 1 6/9

42/72 + 15/9 is 9/4.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 9 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 72 × 1 = 72,
42/72 = 42 × 1/72 × 1 = 42/72
Likewise, for the 2nd fraction, since 9 × 8 = 72,
15/9 = 15 × 8/9 × 8 = 120/72
Add the two like fractions:
42/72 + 120/72 = 42 + 120/72 = 162/72
162/72 simplified gives 9/4
So, 42/72 + 15/9 = 9/4
In mixed form: 21/4

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