Add 90/21 and 40/18, Solve 4 6/21 + 2 4/18 as a fraction

Add 90/21 and 40/18

1^st number: 4 6/21, 2^nd number: 2 4/18

90/21 + 40/18 is 410/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
90/21 = 90 × 6/21 × 6 = 540/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
40/18 = 40 × 7/18 × 7 = 280/126
Add the two like fractions:
540/126 + 280/126 = 540 + 280/126 = 820/126
820/126 simplified gives 410/63
So, 90/21 + 40/18 = 410/63
In mixed form: 632/63

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