SOLUTION: A cell phone company charges a monthly fee of $10 for the first 1000 text messages and 10 cents for each additional text message. Miriam's bill for text messages for the month of J
Algebra.Com
Question 163953This question is from textbook College Algebra
: A cell phone company charges a monthly fee of $10 for the first 1000 text messages and 10 cents for each additional text message. Miriam's bill for text messages for the month of June is $38.50. How many text messages did she send that month?
I can figure out the answer(1285 messages) but I don't know how to write the formula.
Thanks
This question is from textbook College Algebra
Found 2 solutions by josmiceli, gonzo:
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
You have the formula in your head
You just can't get it out
Let = Miriam's monthly bill
Let = the number of text messages sent in the
month of June by Miriam
= the number of text messages over
Miriam's monthly bill is:
dollars
Her monthly bill is $38.50. I'll show it in terms of cents
cents
Subtract from both sides
Add to both sides
messages
----------------------------
It might help to go over the units involved in the 1st
formula which was
dollars
The really stands for ($10/1000 messages)x(1000 messages)
And the other term is really (.1 dollars/message)x(t - 1000 messages)
The units work out to dollars for both terms
----------------------------
You can check the answer
OK
Answer by gonzo(654) (Show Source): You can put this solution on YOUR website!
total messages for the month is 3850 as follows:
-----
let C = cost
let M = number of messages greater than 1000
formula is:
C = $10 + $.01*M
-----
substitute known values in equation.
$38.50 = $10 + $.01*M
subtract $10 from both sides of equation.
$28.5 = $.01*M
divide both sides of the equation by $.01.
2850 = M
-----
looks like number of messages greater than 1000 is 2850.
to prove, substitute in original equation.
-----
$38.50 = $10.00 + $.01*2850
$38.50 = $10.00 + $28.50
$38.50 = $38.50
-----
the value of 2850 for M is good.
total messages for the month would be 2850 + 1000 = 3850.
-----
RELATED QUESTIONS
A cell phone company charges a monthly fee of $10 for the first 1000 text messages and 10 (answered by josmiceli)
A cell company charges a monthly fee of 100 pesos for the first 1000 text messages, and 1 (answered by Cromlix)
Use an inequality and solve.
Braden has budgeted $60 per month for his cell phone. For (answered by josmiceli,josgarithmetic)
Please help! Thank-you!
Have a mixture of chocolate covered pretzels & macadamia nuts. (answered by stanbon)
Your cell phone company offers two text-messaging plans. One plan costs $.25 per text... (answered by MatrixWoman)
On top of the $45 monthly fee, Sam’s cell phone plan charges $0.15 for every text message (answered by MathLover1)
Nick traveled out of the country for a month. He purchased a plan from his cell phone... (answered by josmiceli)
Nick traveled out of the country for a month. He purchased a plan from his cell phone... (answered by Boreal)
For a certain cell phone plan, a customer pays an initial fee of $10.50 plus an... (answered by Ani_g)