Answer:
a) 7(8)+9 (12)
b)7x+45
c )10 hours
Step-by-step explanation:
Hi, to answer this question we have to write an expression
The amount earned by Jason must be equal to the product of the amount he earns per hour during the week (7) and the hours worked during the week (x) ; plus the product of the amount he earns per hour during the weekend ( 9) and the hours worked during the weekend (y):
7x+ 9y
a) substitute x=8 and y=12
7 (8)+ 9 (12)
b) substitute y =5
7 x +9(5) =
7x+ 45 =
c)
Substitute y=5 and the expression must be equal to the amount he needs to buy sports equipment (115):
7x+9 (5)=115
Solving for x:
7x + 45 =115
7x = 115-45
7x = 70
x =70/7
x =10 hours
Answer:
Correct
Step-by-step explanation:
Question 1 - about half of what the white soldiers earned
Question 2 - They were the first all-African American civil war regiment
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Answer:
![a.\ \ \ V=15400(1-0.1)^t](https://tex.z-dn.net/?f=a.%5C%20%5C%20%5C%20V%3D15400%281-0.1%29%5Et)
b. 2 yrs
Step-by-step explanation:
-Given the initial value at time t=0 as $15,400 and the decay rate as 10%.
-The exponential decay is given by the formula;
![y=a(1-r)^x\\\\x-time\\r-decay \ rate\\a-initial \ value\\y-value \ at\ time \ x](https://tex.z-dn.net/?f=y%3Da%281-r%29%5Ex%5C%5C%5C%5Cx-time%5C%5Cr-decay%20%5C%20rate%5C%5Ca-initial%20%5C%20value%5C%5Cy-value%20%5C%20at%5C%20%20time%20%5C%20x)
We can therefore write our decay expression as;
![V=a(1-r)^t\\\\=15400(1-0.10)^t](https://tex.z-dn.net/?f=V%3Da%281-r%29%5Et%5C%5C%5C%5C%3D15400%281-0.10%29%5Et)
Hence, our exponential decay equation is ![V=15400(1-0.1)^t](https://tex.z-dn.net/?f=V%3D15400%281-0.1%29%5Et)
b. Having determined the decay function as
, we make $12465 our y value and solve for time, t;
![V=15400(1-0.1)^t\\\\12465=15400(1-0.1)^t\\\\12465=15400(0.9^t)\\\\0.809416=0.9^t\\\\t=\frac{log \ 0.809416}{log \ 0.9}\\\\=2.0\ yrs](https://tex.z-dn.net/?f=V%3D15400%281-0.1%29%5Et%5C%5C%5C%5C12465%3D15400%281-0.1%29%5Et%5C%5C%5C%5C12465%3D15400%280.9%5Et%29%5C%5C%5C%5C0.809416%3D0.9%5Et%5C%5C%5C%5Ct%3D%5Cfrac%7Blog%20%5C%200.809416%7D%7Blog%20%5C%200.9%7D%5C%5C%5C%5C%3D2.0%5C%20yrs)
Hence, the value of the car will be $12,465 after 2 years
Answer:
30%
Step-by-step explanation:
Since you paid 560 dollars for 8 nights, you can divide to see how much you pay one night. You pay 70 dollars per night. So 30% off from $100 is $70