Answer:
90% confidence interval for the mean commute time of working adult Calgary residents is between a lower limit of 26.72 minutes and an upper limit of 30.28 minutes.
Step-by-step explanation:
Confidence Interval = Mean + or - Error margin (E)
mean = 28.5 minutes
sd = 24.2 minutes
n = 500
degree of freedom = n - 1 = 500 - 1 = 499
confidence level = 90%
t-value corresponding to 499 degrees of freedom and 90% confidence level = 1.64801
E = t × sd/√n = 1.64801 × 24.2/√500 = 1.78
Lower limit = mean - E = 28.5 - 1.78 = 26.72 minutes
Upper limit = mean + E = 28.5 + 1.78 = 30.28 minutes
90% confidence interval is between 26.72 and 30.28 minutes.
Slope-intercept form: y=mx+b, with m being the slope and b being the y-intercept. First, plug in the given slope into the slope form:
y=2x+b
Now, given the coordinates (1,4), you can plug the coordinates into the equation for x and y respectively, to solve for b (the y-intercept).
4=2(1)+b
4=2+b
Subtract 2 from both sides.
2=b
The y-intercept is 2.
Now, plug that into the equation:
y=2x+2
The answer is y=2x+2.
I hope this helps :)
Answer:
whats the question
Step-by-step explanation:
Answer:
Juan imprimió 7 páginas a color.
Step-by-step explanation:
Llamemos "b" a las copias en blanco y negro y "c" a las copias en color.
Juan imprimió 75 páginas. En forma simbólica es:
b + c = 75
b = 75 - c [1]
El costo de impresión de cada página en una biblioteca es de 5 centavos si es en blanco y negro o 50 centavos si es a color. En total pago $6.90. En forma simbólica es:
0.05b + 0.5c = 6.90 [2]
Si reemplazamos [1] en [2],
0.05(75-c) + 0.5c = 6.90
3.75 - 0.05c + 0.5c = 6.90
0.45c = 3.15
c = 7
Juan imprimió 7 páginas a color.
389 children and 224 adults were at the pool that day.
Step-by-step explanation:
Cost of one child ticket = $1.75
Cost of one adult ticket = $2.25
Total people = 613
Total receipts worth = $1184.75
Let,
Number of children = x
Number of adults = y
According to given statement;
x+y=613 Eqn 1
1.75x+2.25y=1184.75 Eqn 2
Multiplying Eqn 1 by 1.75

Subtracting Eqn 3 from Eqn 2

Dividing both sides by 0.50

Putting y=224 in Eqn 1

389 children and 224 adults were at the pool that day.
Keywords: linear equation, subtraction
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