Add 42/72 and 45/42, Solve 42/72 + 1 3/42 as a fraction

Add 42/72 and 45/42

1^st number: 42/72, 2^nd number: 1 3/42

42/72 + 45/42 is 139/84.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 42 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
42/72 = 42 × 7/72 × 7 = 294/504
Likewise, for the 2nd fraction, since 42 × 12 = 504,
45/42 = 45 × 12/42 × 12 = 540/504
Add the two like fractions:
294/504 + 540/504 = 294 + 540/504 = 834/504
834/504 simplified gives 139/84
So, 42/72 + 45/42 = 139/84
In mixed form: 155/84

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