GRE
The remainder when $$2n+1$$ is divided by $$7$$
$$5$$
$$\frac{(k+1)!}{(k-1)!}$$
(k)(k+1)
$$5(2^{x})$$
$$4(3^{x})$$
$$\frac{rs}{t}$$
$$rst$$
The number of different 2-member subsets of a set of 5 members
The number of different 3-member subsets of a set of 5 members
The number of different groups of 2 kittens that can be chosen from a litter of 8 kittens
The number of different groups of 6 puppies that can be chosen from a litter of 8 puppies
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