Answer:
210°F
110 minutes
Step-by-step explanation:
Given that :
Temperature of cake t minutes after being removed from oven :
f(x)=70+140e^-0.024t
Temperature T the timee it is removed ;
At this point, the time t = 0
f(t)=70+140e^-0.024t
f(x)=70+140e^-0.024(0)
= 70 + 140(1)
= 210°F
how long will it take for the cake to reach a temperature of 80oF
80 = 70+140e^-0.024t
80 - 70 = 140*e^-0.024t
10/140 = e^-0.024t
0.0714285 = e^-0.024t
In(0.0714285) = - 0.024t
−2.639057 = - 0.024t
t = 2.639057 / 0.024
t = 109.9607
t = 110 minutes
Two and three hundredths is one and seventeen hundredths less than three and two tenths.
Answer:
28
Step-by-step explanation:
It can be a one digit no.
_
2C1 = 2 (only two even options available)
It can be a 2 digit no.
_ _
The last digit has to be even for the no. to be even.
2C1 × 4C1 = 8 (2C1 for the last digit, 4C1 for the first)
It can be a 3 digit no.
_ _ _
First digit has to be less than 5 to be less than 500, and the last digit has to be even.
1) 2/4 _ 4
2C1 × 3C1 = 6 (2C1 to choose between 2 and 4, 3C1 for the second digit)
2) 1/3 _ 2/4
2C1 × 3C1 × 2C1 = 12 (2C1 to choose between 1 and 3, 3C1 for the second digit, 2C1 to choose between 2 and 4)
Total = 2 + 8 + (6 + 12)
= 28
12(2)+5
Dang, you're an elementary school er? Good grief i'm and 8th grade math one student!
Answer: 30 pounds of coffee beans worth $10.50 per pound was used.
20 pounds of coffee beans worth $13.00 per pound was used.
Step-by-step explanation:
Let x represent the number of coffee beans worth $10.50 per pound that should be mixed.
Let y represent the number of coffee beans worth $13.00 per pound that should be mixed.
50 pounds of beans worth $11.50 per pound is to be made. The total cost of the mixture would be
50 × 11.5 = 575
This means that
10.5x + 13y = 575 - - - - - - - 1
The total number of pounds of each type of coffee used is 50. This means that
x + y = 50
Substituting x = 50 - y into equation 1, it becomes.
10.5(50 - y) + 13y = 575
525 - 10.5y + 13y = 575
- 10.5y + 13y = 575 - 525
2.5y = 50
y = 50/2.5 = 20
x = 50 - 20= 30
