Answer:
95.64% probability that pledges are received within 40 days
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

What is the probability that pledges are received within 40 days
This is the pvalue of Z when X = 40. So



has a pvalue of 0.9564
95.64% probability that pledges are received within 40 days
Answer:
$968
Step-by-step explanation:
x= the money John originally had in his savings account
The statement says that John spent $88 on a radio and 1/4 of what was left on presents for his friends. This means that the remaining money is 3/4 of the total amount minus the money spent on the radio:
3/4(x-88)
Then, it says that of the money remaining, John put 4/11 into a checking account and the last remaining $420 was left to charity. Since, he spent 4/11 of the remining 3/4(x-88), the remaining is 7/11 of that and that remaining is equal to $420 that was the money left at the end:
7/11(3/4(x-88))= 420
21/44(x-88)=420
21/44x-42=420
21/44x=462
x=968
According to this, the money that John originally had in his savings account was $968.
He spent $88 on a radio: 968-88= 880
1/4 of what was left on presents for his friends: 880/4= 220
880-220=660
Of the money remaining, John put 4/11 into a checking account: 660*(4/11)=240
the last remaining $420 was left to charity: 660-240= 420
Answer- i will travel 9 miles in 10 minutes
Answer:
a. 
b. 
c.
or 
d.
or 
e. 
Step-by-step explanation:

Expand

Open brackets


Collect Like Terms


Express 25 as 9 + 16

Factorize:





Expand


Open Brackets

Collect Like Terms


Factorize

Expand the expression in bracket

Factorize:




Factorize


The answer can be in this form of further expanded as follows:

Apply difference of two squares


Express
as 

Expand



The answer can be in this form of further expanded as follows:

Apply difference of two squares


Represent as squares

Apply difference of two squares

Represent as squares

Apply difference of two squares

Answer:
8.75
Step-by-step explanation: