Answer: There are 97 nickels and 108 quarters.
Step-by-step explanation:
Let x = Number of nickels, y = Number of quarters.
As per given,
x+y = 205 ...(i)
0.05x+0.25y = 31.85 ... (ii) [1 nickel = $0.05, 1 quarter = $ 0.25]
Multiply (ii) by 20, we get
x+5y=637 ...(iii)
Eliminate (i) from (iii)
4y = 432
⇒ y = 108 [Divide both sides by 4]
Put value of y in (i), we get
Hence, there are 97 nickels and 108 quarters.
Answer:
1. ( 19.1416, 23.5384,)
2. (0.276348, 0.46651)
3. the sample size = 170.73 approximately 171
4. sample size = 334.07 approximately 334
5. sample of 334 should be taken by manager
Step-by-step explanation:
mean = bar x = 21.34 dollars
size of sample n = 70
standard deviation of sample = 9.22
we use t distribution as the population standard deviation is not known.
95% Confidence interval
1-α = 0.95
α = 0.05
degree of freedom = 70-1 = 69
α/2 = 0.025
using the t distribution tsble,
= 1.9949
confidence interval =
= 21.34 +- (1.9949*1.10200)
= 21.34 + 2.1984, 21.34 - 2.1984
= (23.5384, 19.1416)
the confidence interval of the mean amount spent at the supply store can be written as 19.1416<u<23.5384
2. sixe of those who only have a cat
p = 26/70 = 0.371429
at 90 % confidence interval,
1-α = 0.90
α = 0.10
we use the z table here
z(0.10/2) = Z(0.05)
= 1.645
= 0.371429 +-( 1.645 x 0.0578)
= 0.371429 + 0.095081, 0.371429 - 0.095081
= (0.276348, 0.46651)
3. sd = 10$
margin of erro,r e = 1.50$
α = 0.05
using z table
α/2 = Z0.025
= 1.96
sample size = 1.96² * 10² / 1.50²
= 3.8416 * 100/ 2.25
= 170.73
the sample size is approximately 171
d. we have 0.5 as sample proportion now
margin of error = 0.045
α = 0.10
Zα/2 = 0.05
= 1.645
sample size = 1.645²x0.5(1-0.5) / 0.045²
= 0.676506/0.002025
= 334. 07
sample size = 334
5. sample of 334 should be taken by manager
Answer:
x= 7
Step-by-step explanation:
It's a 45 45 90 triangle
The legs are = x while the hypotenuse is x .
Therefore the answer is 7
Gene earns 2% interest after depositing $150 into his account , Option D.
<h3>What is a Function ?</h3><h3 />A function is a law that relates an independent variable and a dependent variable with each other.
The function given is
f(x) = 0.02 x +150
Option D , Gene earns 2% interest after depositing $150 into his account
So this verbal description matches the function given as it represents , the total account balance of Gene .
Therefore Option D is the correct answer.
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