IAR Math Modeling and Application 2

Question 1

A phone plan charges $20 per month plus $0.10 per text. Which equation models the monthly cost C for t texts?

Accepted Answer

C = 20 + 0.10t

Answer

The fixed $20 is constant and $0.10 multiplies the number of texts t.

Question 2

A car travels at a steady 55 miles per hour. How far does it go in 3.5 hours?

Accepted Answer

192.5 miles

Answer

Distance equals rate times time, so 55 x 3.5 = 192.5 miles.

Question 3

A recipe for 4 servings uses 3 cups of flour. How much flour is needed for 10 servings?

Accepted Answer

7.5 cups

Answer

Set up the proportion 3/4 = x/10, giving x = 7.5 cups.

Question 4

A pool fills at 12 gallons per minute and already holds 50 gallons. Which models total gallons G after m minutes?

Accepted Answer

G = 50 + 12m

Answer

The starting 50 gallons is constant and 12 gallons are added each minute.

Question 5

A store marks up an item costing $40 by 25%. What is the selling price?

Accepted Answer

$50

Answer

A 25% markup adds $10 to the $40 cost, giving $50.

IAR Practice Test