<s>[INST] Ratio word problem with eggs? The eggs in a certain basket are either white or brown. If the ratio of the number of white eggs to the number of brown eggs is $2/3$ , each of the following could be the number of eggs in the basket except.....
A 10
B 12
C 15
D 30
E 60
 [/INST] $$\dfrac 23 = \dfrac 46 = \dfrac 69 = \dfrac{8}{12} = \dfrac{10}{15} = \dfrac {12}{18} = \dfrac {14}{21} = \dfrac {16}{24} = \dfrac{18}{27} = \dfrac{20}{30} = \dfrac{22}{33} = \dfrac{24}{36}$$
For each ratio, the total number of eggs is given by the sum of the numerator with the denominator, ordered as follows  $$\text{sum}\;\dfrac {2n}{3n}: 2n + 3n = 5n: \quad 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, ...$$
Note that $12$ does not appear among them.
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