Add 21/45 and 90/70, Solve 21/45 + 1 20/70 as a fraction

Add 21/45 and 90/70

1^st number: 21/45, 2^nd number: 1 20/70

21/45 + 90/70 is 184/105.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 70 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
21/45 = 21 × 14/45 × 14 = 294/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
90/70 = 90 × 9/70 × 9 = 810/630
Add the two like fractions:
294/630 + 810/630 = 294 + 810/630 = 1104/630
1104/630 simplified gives 184/105
So, 21/45 + 90/70 = 184/105
In mixed form: 179/105

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