This is an awful question. They mean to say the number of hours practicing <em>per week</em> (we'll call it h) varies inversely with the <em>time</em> (t) she runs her event. Unless they mean to imply more practicing makes Tyler slower, in which case she should just get a pizza.
Inverse variation means the product is a constant, we'll call it k.
ht = k
When h = 1 hour t=6 minutes
(1)(6) = k
k = 6 (hour*minutes, but as long as we're consistent we don't need to sweat the unit.)
Decreasing her time by one minute means t = 6 - 1 = 5. We solve for h.
ht = k
h = k/t = 6/5 = 1.2 hours
Answer: 1.2 hours, second choice
C(x) = 400 + 20x - 0.2x²
c(30) = 400 + 20(30) - 0.2(30)²
= 400 + 600 - 0.2(900)
= 1000 - 180
= 820
It costs $820 when 30 radios are produced.
Marginal cost is how much it would cost to make one MORE of the same product so now we find how much it costs to produce 31 radios and compare the two.
c(31) = 400 + 20(31) - 0.2(31)²
= 400 + 620 - 0.2(961)
= 1020 - 192.2
= 827.8 or ≈828.
Now we find the difference which means we subtract the two.
828 - 820 = 8.
Your marginal cost is $8.
To compare we can also do 29 radios.
c(29) = 400 + 20(29) - 0.2(29)² = 811.8 or ≈812
820 - 812 = 8.
Answer:
Tom started out with 57 games but sold 37 of them.
=> Now, Tom has: 57 - 37 =20 games
He put the rest in boxes with 5 games in each.
=> The number of boxes: 20/5 = 4 box
Hope this helps!
:)
You need 2-7 all answered ?