Pre-Assessment: Rational Number Operations
Each of the following student work samples has a mistake.
Identify and explain each mistake.
Problem Student Work Explain the Mistake
Mr. Jackson paid for his purchase of
fishing equipment with $75. He
bought 16 weights and 24 packages
of worms. The cost of each weight
was $1.16, and the cost of each
package of worms was $2.25. How
much change should Mr. Jackson
receive?
$1.16
16
$18.56
$2.25
24
$54.00
$18.56
54.00
$72.56
Mr. Jackson received
$72.56 in change.
A gym offers its members an
optional clean towel service for
$16.40 each month.
The gym has 62 members
that use the towel service.
At the end of the first week,
12 members that use the
towel service had paid the
fee.
The remaining members that
use the towel service paid
during the second week of
the month.
How much money was collected
during the second week of the
month for the towel service?
$16.40
12
$196.80
The gym collected $196.80.
At 2 A.M. in Alaska, the temperature
was 1F. The temperature dropped
3
3
4
degrees each hour after that.
What was the temperature 3 hours
later?
33
1331
44
The temperature 3 hours
later is
3
1
4
degrees.
