A pen and pencil have a total cost of $6. If the pen costs twice as much as the pencil, what is the cost of the pen? Give the rationale and then the answer.
Let's think step by step. Let x be the cost of the pencil. If the pen costs 2 times the cost of the pencil, then it costs 2x. Adding the cost of the pen and pencil we get 2x + x = 3x. Since the total cost is $6 then 3x = $6 therefore x = $6 / 3 = $2. One pen is equal to 2 * x which is 2 * $2 = $4.. The answer is: 4.

Kat gets a 95% on her first math test and an 80% on her second math test. If she wants an average grade of at least 90% in her math class, what does she need to get on her third final math test? Give the rationale and then the answer.
Let's think step by step. Let x = the percent needed on her third math test. (95 + 80 + x) / 3 = 90. (95 + 80 + x) = 270. x = 270 - 95 - 80. x = 95.. The answer is: 95.

There are 14 chickens in the coop, and twice that many in the run. There is 4 less than double the number of chickens free ranging as in the run. How many chickens are free ranging? Give the rationale and then the answer.
Let's think step by step. Coop:14 chickens. Run:14(2) = 28 chickens. Free Range:28(2) - 4 = 52 chickens.. The answer is: 52.