I keep getting a weird answer...can someone help?

These are the fees for sending a package by Media Mail:

$2.41 for the first pound

$0.41 per additional pound for the next six pounds

$0.39 per additional pound after that

For example, a two-pound package costs $2.82 to send by Media Mail.

If a package full of books costs $7.99 to send by Media Mail, how many pounds does the package weigh? Explain your work in complete sentences.

Question

I keep getting a weird answer...can someone help?

These are the fees for sending a package by Media Mail:

$2.41 for the first pound

$0.41 per additional pound for the next six pounds

$0.39 per additional pound after that

For example, a two-pound package costs $2.82 to send by Media Mail.

If a package full of books costs $7.99 to send by Media Mail, how many pounds does the package weigh? Explain your work in complete sentences.

jadebirdfly · Answer

@phi

phi · Answer

can you figure out how much it costs for 7 pounds ?

jadebirdfly · Answer

it costs $4.87, which means there is still 3.12 left

phi · Answer

yes.  and we know the cost of all pounds above 7 lbs, is 0.39 per pound
divide 3.12 by 0.39 to get the number of pounds above 7

jadebirdfly · Answer

oh ok thanks

phi · Answer

you should get 8 extra lbs, so 15 pounds total for the package