GRE
M
1
$$\frac{1}{\frac{1}{a}+\frac{1}{15}+\frac{1}{14}+\frac{1}{13}+\frac{1}{12}}$$
$$\frac{1}{\frac{1}{b}+\frac{1}{15}+\frac{1}{14}+\frac{1}{13}+\frac{1}{12}}$$
$$\frac{a}{b}$$
$$\frac{1}{2}$$
z
3.8
x
The ratio of the cost of 1 of the health magazines to the cost of 1 of the news magazines
$$\frac{4}{5}$$
The greatest possible number of lots minus the least possible number of lots
20
The number of combinations of $$3m$$ objects taken $$m+9$$ at a time
The number of combinations of $$3m$$ objects taken $$2m-9$$ at a time
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