Add 28/42 and 70/45, Solve 28/42 + 1 25/45 as a fraction

Add 28/42 and 70/45

1^st number: 28/42, 2^nd number: 1 25/45

28/42 + 70/45 is 20/9.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 42 × 15 = 630,
28/42 = 28 × 15/42 × 15 = 420/630
Likewise, for the 2nd fraction, since 45 × 14 = 630,
70/45 = 70 × 14/45 × 14 = 980/630
Add the two like fractions:
420/630 + 980/630 = 420 + 980/630 = 1400/630
1400/630 simplified gives 20/9
So, 28/42 + 70/45 = 20/9
In mixed form: 22/9

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