Answer: Stephanie read more than 7 books because 8 points for 9 books each is equal to 72 points, which is the total amount of books she read.
Step-by-step explanation:
72 ÷ 8 × 9
x = 9
Hope this helped! :D
9514 1404 393
Answer:
Step-by-step explanation:
The decay factor is 1 -25% = 0.75 per hour, so the exponential equation can be written ...
r(t) = 1450·0.75^t . . . . . milligrams remaining after t hours
__
a) After 4 hours, the amount remaining is ...
r(4) = 1450·0.75^4 ≈ 458.79 . . . mg
About 459 mg will remain after 4 hours.
__
b) To find the time it takes before the amount remaining is less than 5 mg, we need to solve ...
r(t) < 5
1450·0.75^t < 5 . . . . use the function definition
0.75^t < 5/1450 . . . . divide by 1450
t·log(0.75) < log(1/290) . . . . . take logarithms (reduce fraction)
t > log(1/290)/log(0.75) . . . . . divide by the (negative) coefficient of t
t > 19.708
It will take about 20 hours for the amount of the drug remaining to be less than 5 mg.
Y=2,137.00-(15.15*X)+(33.09*X)
Its simple arithmetic when you get down to it. The $2,137 won't change because it is the base rate per month, meaning even if they don't make any units they will still earn that much in the month. You subtract from that the cost to make a unit, in this case it is $15.15 per unit, so you multiply the cost by number of units to get the month's total costs. Then add the total month's profits by multiplying the number of units by the profits of one unit.