Add 70/21 and 25/40, Solve 3 7/21 + 25/40 as a fraction

Add 70/21 and 25/40

1^st number: 3 7/21, 2^nd number: 25/40

70/21 + 25/40 is 95/24.

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,
70/21 = 70 × 40/21 × 40 = 2800/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
25/40 = 25 × 21/40 × 21 = 525/840
Add the two like fractions:
2800/840 + 525/840 = 2800 + 525/840 = 3325/840
3325/840 simplified gives 95/24
So, 70/21 + 25/40 = 95/24
In mixed form: 323/24

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