Answer:
2/π ≈ 0.637 m/s
Step-by-step explanation:
The rate of change of area with respect to time is ...
A = πr²
dA/dt = 2πr·dr/dt
Filling in given values in the above equations, we can find r and dr/dt.
25π = πr² ⇒ r = 5
20 = 2π·5·dr/dt
dr/dt = 20/(10π) = 2/π . . . . meters per second
The radius is increasing at the rate of 2/π ≈ 0.637 meters per second.
Answer:
Speedy Taxis
Step-by-step explanation:
I solved this by using a graphing calculator. Speedy Taxis shows the least cost for x=30.
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You can figure the cost of each for x=30
1.5(30) = 45
1.1(30)+11.5 = 33+11.5 = 44.5 . . . . . lowest cost
1.25(30)+8 = 37.5+8 = 45.5
Speedy Taxis is the cheapest for a trip of 30 miles.
Remark
You have 40 dollars to spend.
<em><u>AT & T</u></em>
Let the number of minutes = M
A. 20 + 0.10*M ≤ 40
B. 20 + 0.10*M ≤ 40 Subtract 20 from both sides.
20 - 20 + 0.10M ≤ 40 - 20
0.10M ≤ 20 Divide by 0.10
0.10M/0.10 ≤20/0.10
M≤ 200 minutes.
Verizon
A
15 + ( M ≥ 300)*0.50 ≤ 40
B
15 + ( M ≥ 300)*0.50 ≤ 40 Subtract 15 from both sides.
(M≥300)*0.50 ≤ 25
(M≥300) ≤ 50 minutes.
This last one is a good deal more complicated. What it means is that if you are under 300 minutes, you pay only 15 dollars. If you are over 300 minutes, you can only go 50 more minutes before over extend your budget.
Part C
These are alike in that they have a flat rate associated with them and both have a budgeted amount that has to be obeyed.
They are quite different in what they offer. The second plan is for people who use their cell phone quite a bit. For people like us (emergency only), the first plan is much better. We would always be within our 40 dollar limit. We don't use our cell but maybe 10 - 15 minutes a month on average.
Part D
I can't answer this for you. It depends on where you live and who offers you the best coverage. I would pick the first one, but that doesn't mean that it would be best for you.
Answer: you would simple multiply the cost c which is fifty bucks times the number of p people
Step-by-step explanation: how much would it cost for 6 people to go to the fair to solve this you would just set up the equation 6 * 50 and solve from there
10 and 2.
GCF of 2 is 10 and 2?