Add 90/45 and 21/70
1st number: 2 0/45, 2nd number: 21/70
90/45 + 21/70 is 23/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
90/45 = 90 × 14/45 × 14 = 1260/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630 - Add the two like fractions:
1260/630 + 189/630 = 1260 + 189/630 = 1449/630 - 1449/630 simplified gives 23/10
- So, 90/45 + 21/70 = 23/10
In mixed form: 23/10
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