speed with no wind = s
speed with wind = s + 5
speed against wind = s - 5
time = t
speed = distance/time
distance = speed * time
With wind, time = t, speed = s + 5, distance = 50
50 = (s + 5)t
Against wind, time = t, speed = s - 5, distance = 30
30 = (s - 5)t
t = 30/(s - 5)
50 = (s + 5) * 30/(s - 5)
50(s - 5) = (s + 5) * 30
50s - 250 = 30s + 150
20s = 400
s = 20
Answer: 20 mph
Answer:
The amount in account after 7 years of investment is $1478.4
Step-by-step explanation:
Given as :
The principal invested in account by Jamie = p = $1200
The rate of interest = r = 3% compounded annually
The Time period of investment = t= 7 years
Let The Amount in Jamie account = $ A
<u>For continuous compounding</u>
Amount = Principal × 
Or, A = p ×
Or, A = $1200 × 
Or, A = $1200 × 
Or, A = $1200 × 1.232
∴ A = $1478.4
So, The amount after continuous compounding = A = $1478.4
Hence , The amount in account after 7 years of investment is $1478.4 Answer
Answer:
At least 6907 people.
Step-by-step explanation:
Population std deviation = sigma= 10.6
Since population std deviation is known, we can use normal probability table to get sample size from confidence interval.
The sample mean weight loss is within 0.25 lb of the true population mean.
Hence margin of error < 0.25
Margin of error = z critical (std dev/n) where n = sample size
Z critical for 95% = 1.96
Hence 0.25 >1.96(10.6)/sq rt n
Simplify to get
sq rt n > 1.96(10.6)/0.25 = 83.104
Square both the sides to get
n > 83.104 square = 6906.27
i.e. sample size should be atleast 6907.
Answer:
$18500 at 6% and $28500 at 8%
Step-by-step explanation:
Let x represent the amount invested at 6%. Then x+10000 is the amount invested at 8%. The total income from the two investments is the sum of the products of the amount invested and the interest rate:
x·6% +(x+10000)·8% = 3390
0.14x + 800 = 3390 . . . . . . . . collect terms
0.14x = 2590 . . . . . . . . . . . . . .subtract 800
2590/0.14 = x = 18500 . . . . . divide by the coefficient of x
Sue has invested $18500 at 6% and $28500 at 8%.
