Add 7/40 and 84/21
1st number: 7/40, 2nd number: 4 0/21
7/40 + 84/21 is 167/40.
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,
7/40 = 7 × 21/40 × 21 = 147/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
84/21 = 84 × 40/21 × 40 = 3360/840 - Add the two like fractions:
147/840 + 3360/840 = 147 + 3360/840 = 3507/840 - 3507/840 simplified gives 167/40
- So, 7/40 + 84/21 = 167/40
In mixed form: 47/40
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