Add 25/21 and 70/40, Solve 1 4/21 + 1 30/40 as a fraction

Add 25/21 and 70/40

1^st number: 1 4/21, 2^nd number: 1 30/40

25/21 + 70/40 is 247/84.

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,
25/21 = 25 × 40/21 × 40 = 1000/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
70/40 = 70 × 21/40 × 21 = 1470/840
Add the two like fractions:
1000/840 + 1470/840 = 1000 + 1470/840 = 2470/840
2470/840 simplified gives 247/84
So, 25/21 + 70/40 = 247/84
In mixed form: 279/84

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