Add 30/21 and 8/40, Solve 1 9/21 + 8/40 as a fraction

Add 30/21 and 8/40

1^st number: 1 9/21, 2^nd number: 8/40

30/21 + 8/40 is 57/35.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 21 × 40 = 840,
30/21 = 30 × 40/21 × 40 = 1200/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
8/40 = 8 × 21/40 × 21 = 168/840
Add the two like fractions:
1200/840 + 168/840 = 1200 + 168/840 = 1368/840
1368/840 simplified gives 57/35
So, 30/21 + 8/40 = 57/35
In mixed form: 122/35

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