Add 24/21 and 10/40, Solve 1 3/21 + 10/40 as a fraction

Add 24/21 and 10/40

1^st number: 1 3/21, 2^nd number: 10/40

24/21 + 10/40 is 39/28.

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,
24/21 = 24 × 40/21 × 40 = 960/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
10/40 = 10 × 21/40 × 21 = 210/840
Add the two like fractions:
960/840 + 210/840 = 960 + 210/840 = 1170/840
1170/840 simplified gives 39/28
So, 24/21 + 10/40 = 39/28
In mixed form: 111/28

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