Add 3/40 and 84/21
1st number: 3/40, 2nd number: 4 0/21
3/40 + 84/21 is 163/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
3/40 = 3 × 21/40 × 21 = 63/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
84/21 = 84 × 40/21 × 40 = 3360/840 - Add the two like fractions:
63/840 + 3360/840 = 63 + 3360/840 = 3423/840 - 3423/840 simplified gives 163/40
- So, 3/40 + 84/21 = 163/40
In mixed form: 43/40
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