Add 3/40 and 84/63, Solve 3/40 + 1 21/63 as a fraction

Add 3/40 and 84/63

1^st number: 3/40, 2^nd number: 1 21/63

3/40 + 84/63 is 169/120.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 63 is 2520

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 40 × 63 = 2520,
3/40 = 3 × 63/40 × 63 = 189/2520
Likewise, for the 2nd fraction, since 63 × 40 = 2520,
84/63 = 84 × 40/63 × 40 = 3360/2520
Add the two like fractions:
189/2520 + 3360/2520 = 189 + 3360/2520 = 3549/2520
3549/2520 simplified gives 169/120
So, 3/40 + 84/63 = 169/120
In mixed form: 149/120

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