Add 21/28 and 90/75
1st number: 21/28, 2nd number: 1 15/75
21/28 + 90/75 is 39/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 75 is 2100
Next, find the equivalent fraction of both fractional numbers with denominator 2100 - For the 1st fraction, since 28 × 75 = 2100,
21/28 = 21 × 75/28 × 75 = 1575/2100 - Likewise, for the 2nd fraction, since 75 × 28 = 2100,
90/75 = 90 × 28/75 × 28 = 2520/2100 - Add the two like fractions:
1575/2100 + 2520/2100 = 1575 + 2520/2100 = 4095/2100 - 4095/2100 simplified gives 39/20
- So, 21/28 + 90/75 = 39/20
In mixed form: 119/20
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