Add 84/10 and 21/45, Solve 8 4/10 + 21/45 as a fraction

Add 84/10 and 21/45

1^st number: 8 4/10, 2^nd number: 21/45

84/10 + 21/45 is 133/15.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 45 is 90

Next, find the equivalent fraction of both fractional numbers with denominator 90
For the 1st fraction, since 10 × 9 = 90,
84/10 = 84 × 9/10 × 9 = 756/90
Likewise, for the 2nd fraction, since 45 × 2 = 90,
21/45 = 21 × 2/45 × 2 = 42/90
Add the two like fractions:
756/90 + 42/90 = 756 + 42/90 = 798/90
798/90 simplified gives 133/15
So, 84/10 + 21/45 = 133/15
In mixed form: 813/15

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