Real-Life Math
Billy Winkle just completed his driving test. For the past hour,
you've been watching him like a hawk, seeing where he got it right, and
where he zigged when he should have zagged.
"Hey, how did I do?" he
asks you as he looks out the window.
"Well, Billy," you mumble, "it's
going to be close. You made a few mistakes out there."
Billy is silent
as you make your way into the driving center. He seems sure he failed.
"Math
is obviously a consideration in driving instruction," says Kenny Morse, a
driving instructor. "In any job that involves testing, passing and failing,
there is a numerical consideration."
Here is what Billy's test
sheet looks like:
| Demerit | Penalty | Times |
Failure to check blind
spot while changing lanes | -2.5 | 2 |
| Sloppy parallel parking technique | -4.0 | 1 |
| Excessive speed | -2.5 | 6 |
Failure to perform circle-check before
stepping into car | -2.5 | 1 |
In this case, road tests are graded on a 125-point scale. To pass
the test, an applicant must receive 75 percent on his or her road test.
Your
job is to figure out whether Billy passed.