Add 81/18 and 90/70, Solve 4 9/18 + 1 20/70 as a fraction

Add 81/18 and 90/70

1^st number: 4 9/18, 2^nd number: 1 20/70

81/18 + 90/70 is 81/14.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 70 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 18 × 35 = 630,
81/18 = 81 × 35/18 × 35 = 2835/630
Likewise, for the 2nd fraction, since 70 × 9 = 630,
90/70 = 90 × 9/70 × 9 = 810/630
Add the two like fractions:
2835/630 + 810/630 = 2835 + 810/630 = 3645/630
3645/630 simplified gives 81/14
So, 81/18 + 90/70 = 81/14
In mixed form: 511/14

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