Question

A student took 60 minutes to answer a combination of 20 multiple choice and extended response choice questions she took two minutes to anwer each multiple choice and 6 minutes to anwaer each extended response.
A) write a system of equations to model the relationship between the number of multiple choice questions M and number of extended response questions R
B) how many of each type of question was on the test

Answer 1

20 = m + r
60 = 2m + 6r

Using substitution, you would subtract R from both sides in the first equation.

20 - r = m

Substitute (20 - r) for m in the second equation.

60 = 2(20 - r) + 6r

Distribute the 2

60 = 40 - 2r +6r

Combine like terms.

20 = 4r

Divide both sides by 4

5 = r

Now put R back into the first equation.

20 - 5 = m

15 = m

There were 15 multiple choice and 5 extended response questions.

Answer 2

The average rate of change of g(x) between x = 4 and x = 7 is . Which statement must be true?