# SAT Math Multiple Choice Question 374: Answer and Explanation

### Test Information

Question: 374

14. Three airplanes depart from three different airports at 8:30 AM, all travelling to Chicago O'Hare International Airport (ORD). The distances the planes must travel are recorded in the following table.

From Distance to Chicago (ORD)
Kansas City (MCI) 402
Boston (BOS) 864
Miami (MIA) 1,200

The plane traveling from Boston traveled at an average speed of 360 mph. The plane traveling from Kansas City arrived at 10:34 AM. How many minutes before the plane from Boston arrived did the plane from Kansas City arrive?

• A. 20
• B. 28
• C. 42
• D. 144

Explanation:

A

Difficulty: Medium

Category: Problem Solving and Data Analysis / Rates, Ratios, Proportions, and Percentages

Strategic Advice: Questions that involve distance, rate, and time can almost always be solved using the formula Distance = rate × time.

Getting to the Answer: Use the speed, or rate, of the plane from Boston, 360 mph, and its distance from Chicago, 864 mi, to determine when it arrived. You don't know the time, so call it t.

This means it took 2.4 hours for the plane to arrive. This is more than 2 full hours, so multiply 2.4 by 60 to find the number of minutes it took: 60 × 2.4 = 144 minutes. Now determine how long it took the plane from Kansas City. It left at 8:30 AM and arrived at 10:34 AM, so it took 2 hours and 4 minutes, or 124 minutes. This means the plane from Kansas City arrived 144 – 124 = 20 minutes before the plane from Boston.