Answer:
Answer: The average speed is 54 miles per hour.
I believe the answer to 1/7 times 20 would be 2.9 that is rounded to the nearest tenth but if your rounding to the nearest whole number it would be 3
As for 1/9 of 82 it would be 9.1 rounded to the nearest tenth and it would be 9 rounded to the nearest whole number.
If he spends 1/4 reading the news, then he spends 3/4 reading the other stuff
3/4 * 8/9 = 24/36 = 2/3 of an hr ...time spent reading sports and comics
(2/3) / 2 =
2/3 * 1/2 = 2/6 reduces to 1/3....so he spends 1/3 of an hour (or 20 minutes) reading the comics
1 nickels =$0.05
1 dime= $0.1
let the number of nickels be x and that of dimes be y.
total number of coins is given by:
x+y=42
hence:
y=42-x.......i
total amount of cash will be:
0.05x+0.1y=3.30.........ii
substituting i in ii we get:
0.05x+0.1(42-x)=3.30
0.05x+4.2-0.1x=3.3
-0.05x=-0.9
x=-0.9/(-0.05)
x=18
hence the the number nickels is x=18, the number of dimes will be y=42-x=42-18=24
Answers:
- a = 475
- r = -0.5
- f(3) = 59.4
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Explanation:
Any exponential function is of the form y = a*b^x
Comparing that to y = 475*(0.5)^x, we see that a = 475 and b = 0.5
Set b equal to 1+r and solve for r
1+r = 0.5
r = 0.5-1
r = -0.5
The negative r value tells us that the growth rate is -50%, in other words, we have a 50% decay rate. The amount drops by 50% each time x goes up by 1. This is the same as saying the amount cuts in half each time x goes up by 1.
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Lastly, plug in x = 3 to find f(3)
f(x) = 475(0.5)^x
f(3) = 475(0.5)^3
f(3) = 59.375
f(3) = 59.4
