Add 80/42 and 75/90, Solve 1 38/42 + 75/90 as a fraction

Add 80/42 and 75/90

1^st number: 1 38/42, 2^nd number: 75/90

80/42 + 75/90 is 115/42.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 42 × 15 = 630,
80/42 = 80 × 15/42 × 15 = 1200/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
75/90 = 75 × 7/90 × 7 = 525/630
Add the two like fractions:
1200/630 + 525/630 = 1200 + 525/630 = 1725/630
1725/630 simplified gives 115/42
So, 80/42 + 75/90 = 115/42
In mixed form: 231/42

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