AMC 10 2021 (Mock) Problems

Revision as of 22:14, 29 November 2021 by Shiamk (talk | contribs) (Problem 5)

Problem 1

Given that $A + B - C = 2020, B + C - A = 2021,$ and $A + C - B = 2022,$ what is the value of $A + B + C - 2020 - 2021 - 2022$?


$\mathrm{(A) \ } 0\qquad \mathrm{(B) \ } 2020\qquad \mathrm{(C) \ } 2021\qquad \mathrm{(D) \ } 2022\qquad \mathrm{(E) \ } 6063$


Problem 2

A bag of marbles consists of $4$ red marbles and $3$ blue marbles. Each of these $7$ marbles are pulled out one at a time. What is the probability that the $5th$ marble pulled out is red?


$\mathrm{(A) \ } \frac{1}{5}\qquad \mathrm{(B) \ } \frac{3}{7}\qquad \mathrm{(C) \ } \frac{1}{2}\qquad \mathrm{(D) \ } \frac{4}{7}\qquad \mathrm{(E) \ } \frac{4}{5}$


Problem 3

Meena has $11$ snakes, $6$ are purple and the rest are green. Some of the snakes are poisonous. She knows that $2$ of the poisonous snakes are green and the number of poisonous snakes which are purple is double the amount of poisonous snakes that are green. How many snakes are not poisonous?


$\mathrm{(A) \ } 3 \qquad \mathrm{(B) \ } 4 \qquad \mathrm{(C) \ } 5\qquad \mathrm{(D) \ }6\qquad \mathrm{(E) \ }7$


Problem 4

At a birthday celebration consisting of $K$ kids, each of the $K$ kids purchase $S$ soda cans except for the birthday kid, who purchases $2S$ soda cans. $S$ soda cans cost $Q$ quarters. How many dollars were spent total on the soda cans?

$\mathrm{(A) \ } \frac{(K - 1)Q}{6}\qquad \mathrm{(B) \ } \frac{(K - 1)Q}{4}\qquad \mathrm{(C) \ } \frac{KQ}{4}\qquad \mathrm{(D) \ } \frac{(K + 1)Q}{4}\qquad \mathrm{(E) \ } \frac{(K + 1)Q}{2}$


Problem 5

Let a quadratic $Ax^2 + Bx + C$ have roots $a$ and $b$. Given that $a$ and $b$ are integers, and $\frac{1}{a}