Add 40/21 and 72/40
1st number: 1 19/21, 2nd number: 1 32/40
40/21 + 72/40 is 389/105.
Steps for adding fractions
- 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,
40/21 = 40 × 40/21 × 40 = 1600/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
72/40 = 72 × 21/40 × 21 = 1512/840 - Add the two like fractions:
1600/840 + 1512/840 = 1600 + 1512/840 = 3112/840 - 3112/840 simplified gives 389/105
- So, 40/21 + 72/40 = 389/105
In mixed form: 374/105
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