I would love some help please...At a private school in addition to tuition, students are charged for lab fees and supplies as shown:
Kgtn = $230
1st = $271
2nd= $300
4th = $340
6th = $369
7th = $385
Let f(n) be the per student charge (in dollars) for lab fees and supplies for nth grade, kindergarten is shown by n=0. A model for this situation is f(n)=228 4√n+1 Estimate for what grade the per student charge for lab fees and supplies is $394.

Question

I would love some help please...At a private school in addition to tuition, students are charged for lab fees and supplies as shown: 
Kgtn =  $230
1st  =	$271
2nd=	$300
4th =	$340
6th =	$369
7th =	$385
Let f(n) be the per student charge (in dollars) for lab fees and supplies for nth grade, kindergarten is shown by n=0.  A model for this situation is f(n)=228 4√n+1  Estimate for what grade the per student charge for lab fees and supplies is $394.

dumbcow · Answer

is that sqrt(n) or sqrt(n+1)

anonymous · Answer

n+1

anonymous · Answer

sorry should have put (n+1)

dumbcow · Answer

whats in between the 8 and 4?
could you rewrite f(n)

anonymous · Answer

= 228 4√n+1)  
There is a space btwn 228 then a small raised 4 before the radical

dumbcow · Answer

oh ok
f(n) = 394, solve for n
$$\sqrt[4]{n+1} = \frac{394}{228}$$
$$n+1 = (1.728)^{4}$$
$$n=7.92$$

dumbcow · Answer

so in other words, 8th grade :)

anonymous · Answer

but wait i get 8.916 for (1.728)^4

dumbcow · Answer

yes but that equals n+1
subtract 1 on both sides...

anonymous · Answer

got it...thank you  si much

anonymous · Answer

so much