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# SAT Mean, Median, and Mode

The average of $$11$$ numbers is $$205.$$ When another number is introduced, the average of the $$12$$ numbers is also $$205.$$ What is the $$12\text{th}$$ number?

(A) $$\ \ \frac{11}{205}$$

(B) $$\ \ \frac{12}{11}$$

(C) $$\ \ 11$$

(D) $$\ \ 23$$

(E) $$\ \ 205$$

If the average (arithmetic mean) of $$5, 10, 15, 20,$$ and $$x$$ is $$53$$, what is the value of $$x$$?

(A) $$\ \ 3$$
(B) $$\ \ 50$$
(C) $$\ \ 53$$
(D) $$\ \ 215$$
(E) $$\ \ 265$$

$$9, 80, 3, 25, 3, 25, 25, 9$$

If $$x$$ is the median of the list above and $$y$$ is the mode, which of the following is $$x+y?$$

(A) $$\ \ 34$$
(B) $$\ \ 39$$
(C) $$\ \ 42$$
(D) $$\ \ 50$$
(E) $$\ \ 97$$

Anna's average (arithmetic mean) on three tests is $$70$$. What grade does she need on her fourth test to raise her average to $$75$$?

(A) $$\ \ 70$$
(B) $$\ \ 75$$
(C) $$\ \ 80$$
(D) $$\ \ 85$$
(E) $$\ \ 90$$

Oliver drove $$600$$ kilometers at $$60$$ km/hr. He then sped up and drove $$1680$$ kilometers at $$120$$ km/hr. What was his average speed, in km/hr, for the entire trip?

(A) $$\ \ 90$$
(B) $$\ \ 95$$
(C) $$\ \ 100$$
(D) $$\ \ 105$$
(E) $$\ \ 420$$

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