Question

at the beginning of the school year, billys dad deposited $100 in billys school lunch account. each time billy buys hot lunch, $4 is deducted from the account balance. the function b(h) represents the balance, in dollars, of billys lunch account after he buys hot lunch h times. what is the domain of b(h)? all real numbers less than or equal to 100 all real numbers from 0 to 25 all whole numbers less than or equal to 100 all whole numbers from 0 to 25

Explanation:

Step1: Find max number of lunches

Set balance to 0: $100 - 4h = 0$
Solve for $h$: $4h = 100$ → $h = \frac{100}{4} = 25$

Step2: Define valid $h$ values

$h$ counts lunch purchases, so it must be a whole number (0,1,2,...,25).

Answer:

all whole numbers from 0 to 25