Add 21/70 and 15/4
1st number: 21/70, 2nd number: 3 3/4
21/70 + 15/4 is 81/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 4 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
21/70 = 21 × 2/70 × 2 = 42/140 - Likewise, for the 2nd fraction, since 4 × 35 = 140,
15/4 = 15 × 35/4 × 35 = 525/140 - Add the two like fractions:
42/140 + 525/140 = 42 + 525/140 = 567/140 - 567/140 simplified gives 81/20
- So, 21/70 + 15/4 = 81/20
In mixed form: 41/20
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