Answer:
yes
Step-by-step explanation:
Answer:
40 girls 20 boys i think / guess
Step-by-step explanation:
Answer:
b = -7
Step-by-step explanation:
The formula for Average speed = 
The car travels 80 km in 1 hour.
Then the car travels 90 km in 2 hours.
And finally the car travels 76 km in 1 hour
So the total distance covered by the car = 80 + 90 + 76 = 246 km
The total time taken to cover this distance = 1 + 2 + 1 = 4 hours.
So average speed = 
The average speed of the car is 61.5 km / h
Answer:
The answer is false
Step-by-step explanation:
In a sample above 30 obs like this the confidence interval is defined as
X+- t* (s/sqrt(n)) where X is the mean t the tvalue for a given confidence level, n the size of sample and s standar deviation.
To find de appropiate value of t we must see the T table where rows are degrees of freedom and columns significance level
The significance is obtained:
significance = 1 - confidence level = 1 - 0.9 = 0.10
Degrees of freedom (df) for the inteval are
df = n - 1 = 18 - 1 = 17
So we must look for the value of a t with 17 values and significance of 0.10 which in t table is 1.740 not 1.746 ( thats the t for 16 df)
