Add 45/20 and 21/7
1st number: 2 5/20, 2nd number: 3 0/7
45/20 + 21/7 is 21/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
45/20 = 45 × 7/20 × 7 = 315/140 - Likewise, for the 2nd fraction, since 7 × 20 = 140,
21/7 = 21 × 20/7 × 20 = 420/140 - Add the two like fractions:
315/140 + 420/140 = 315 + 420/140 = 735/140 - 735/140 simplified gives 21/4
- So, 45/20 + 21/7 = 21/4
In mixed form: 51/4
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