The rates that Zack charges for babysitting are as follows:
-- $2.50 per hour for the first child, and
-- $0.75 per hour for each additional child.
Fill in the values below to show Zack's hourly charges for
babysitting one, two, and three children.
1 child: $
2 children: $
3 children: $
2.50
3.25
4.00
Right! Your answers, $2.50 per hour, $3.25 per hour, and $4.00 per hour, are correct.
The student got this item correct.
2.50
3.25
3.25
Sorry, that's not right. Your first two answers, $2.50 per hour and $3.25 per hour, are correct. However, the rate that Zack charges for supervising three children is higher than the rate for supervising two.
Student added in the 75 cents only for the second child.
3.25
4.00
4.75
You are close, but that's not quite right. It's true that Zack charges an extra $.75 per hour to supervise each additional child, but he only charges $2.50 per hour to supervise one child.
Student added in the additional charge for the first
child, but did everything else right.
3.25
4.00
4.00
Sorry, that's not right. Zack charges $2.50 per hour to supervise one child, and an extra $.75 per hour to supervise each additional child.
Student added in the additional charge for the
first child, added it once more, but then didn't
add it for the third child.
2.50
5.00
7.50
Sorry, that's not right. You are correct that Zack charges $2.50
per hour to supervise the first child. But he only charges an extra $.75 per hour to supervise each additional child.
Student assumed the rate was the same with each additional child.
Sorry, that's not right. Zack charges $2.50 per hour to supervise one
child, and $.75 per hour to supervise each additional child. The correct answers, for one, two, and three
children are: $2.50, $3.25, and $4.00.
The student got this item incorrect.
VerbalRuleArithmetic
ExamplesArithmetic
TableArithmetic
ModelArithmetic