Add 90/21 and 45/20
1st number: 4 6/21, 2nd number: 2 5/20
90/21 + 45/20 is 183/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
90/21 = 90 × 20/21 × 20 = 1800/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
45/20 = 45 × 21/20 × 21 = 945/420 - Add the two like fractions:
1800/420 + 945/420 = 1800 + 945/420 = 2745/420 - 2745/420 simplified gives 183/28
- So, 90/21 + 45/20 = 183/28
In mixed form: 615/28
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