Real-Life Math -- Solution
Last week, the police called your office. They don't have the resources
to watch over a witness that they have enrolled in their witness protection
program, and they've asked for your help. Here's the invoice of all the expenses
you've incurred while guarding the witness.
March 1
Hourly
wage: 9 hours x $45 per hour = $405
Mileage: 50 x $0.65 per mile = $32.50
Cigarettes:
$8.39
Phone call: 3 x $0.50 per minute = $1.50
Subtotal: $405
+ $32.50 + $8.39 + $1.50 = $447.39
March 2
Hourly
wage: 10 hours x $45 per hour = $450
Restaurant food: $50
Mileage:
35 x $0.65 per mile = $22.75
Phone call: 5 x $0.50 = $2.50
Mileage:
45 x $0.65 = $29.25
Subtotal: $450 + $50 + $22.75 + $2.50
+ $29.25 = $554.50
March 3
Hourly wage:
10 hours x $45 per hour = $450
Mileage: 45 x $0.65 per mile = $29.25
Hotel
fee: 3 x $150 = $450
Mileage: 5 x $0.65 per mile = $3.25
Subtotal: $450
+ $29.25 + $450 + $3.25 = $932.50
Total: $447.39 + $554.50
+ $932.50 = $1,934.39
The total invoice is $1,197.15
for three days. That might seem like a lot, but it's not out of the ordinary.
Besides using math for billing, private investigators also use math
when taking measurements and evaluating evidence.
"You use math at
an accident site," says Sheila Klopper. "It could be a scene at somebody's
house or business. We have to go in and diagram it for use in court, and it
has to be to scale."
When things get complicated, Klopper gets experts
to help her out. A former engineer does a lot of diagrams of accident scenes
for her. For financial matters, she sometimes hires forensic accountants.