Alec is climbing a 14 foot ladder where the rungs are 3/4 of a foot apart. there is one foot of space on each end of the ladder before the first and last rung. how many rungs are on the ladder that alec is climbing including the first and last one?

Alec is climbing 17 rungs on the ladder of 14 feet ( including first and last rung ) .

Step-by-step explanation:

Given:

Length of the ladder = 14 foot

Distance between Rungs in ladder =  

There is one foot of space on each end of the ladder before the first and last rung .  

To Find:

Number of  rungs are on the ladder =?

Solution:

Let us assume there are 3 rungs. Between 3 rungs there will be two spaces. between four rungs there will be 3 spaces , so between n + 1  rungs there will be n spaces.

Given that length of the ladder = 14 feet

There is one foot of space on each end before the first and last rung.

So length of the ladder between first and last rung = 14 – 2  ( 1 foot of each side) = 12 feet

As distance between each rung =

Number of    spaces in ladder of 12 feet =

Number of    spaces in ladder of 12 feet=  

Number of    spaces in ladder of 12 feet=

Number of    spaces in ladder of 12 feet =16

And as for n spaces there will be n + 1 rungs, so for 16 spaces there will be 16 + 1 = 17 rungs.

d. 24+-0.114

step-by-step explanation:

the question requires us to calculate the approximate 95% confidence interval for the mean number of ounces of ketchup per bottle in the sample given the following statistics;

sample mean = 24

standard deviation, σ = 0.4

sample size , n = 49

the confidence interval for a population mean is calculated using the formula;

sample mean ± z-score*(σ/sqrt(n))

the z-score associated with a 95% confidence interval, from the standard normal tables, is;

1.96

substituting these values into the formula;

24 ± 1.96*(0.4/7)

= 24 ± 0.112

from the alternatives given, choice d is closest to the above expression;