Answer:
4 hours. 1 3/4 is about 2, and 2 1/4 rounds to 2. 1/4 would round to 0, but it would not affect the estimate's accuracy much because we rounded up by 1/4 on 1 3/4 already. Philipe spent about 4 hours on activities.
Step-by-step explanation:
Answer:
Step-by-step explanation:
The confidence interval for the population mean x can be calculated as:
Where x' is the sample mean, s is the population standard deviation, n is the sample size and 
is the z-score that let a proportion of 
on the right tail.
is calculated as: 100%-99%=1%
So, 
Finally, replacing the values of x' by 308, s by 17, n by 15 and by 2.576, we get that the confidence interval is:
Answer:20cm
Step-by-step explanation:
If the blue ribbon is 9cm shorter you’re just subtracting 29-9 which is 20cm.
Answer:
Step-by-step explanation:
To solve this problem you need the function
h(t) = -16t2 + v0t + h0
where t = time
v0 is the initial velocity, which in our case is 0
h0 = initial height, which in our case is 256
h(t) = 0 since we want to know when the ball will hit the ground.
0 = -16 t2 + 256
And we can solve for t
If we rearrange the terms we see that this is a difference of 2 squares
0 = 256 - 16t2
0 = (16-4t)(16+4t)
Setting each factor = 0
16-4t=0 16+4t=4
t = 4 t = -4
The second solution is discarded as time cannot be negative.
So the ball will hit the ground in 4 seconds.
The answer is 258 pennies
