Add 72/90 and 40/42
72/90 + 40/42 is 184/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
72/90 = 72 × 7/90 × 7 = 504/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
40/42 = 40 × 15/42 × 15 = 600/630 - Add the two like fractions:
504/630 + 600/630 = 504 + 600/630 = 1104/630 - 1104/630 simplified gives 184/105
- So, 72/90 + 40/42 = 184/105
In mixed form: 179/105
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