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
 and standard deviation  , the zscore of a measure X is given by:
, 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
 has a pvalue of 0.9564
95.64% probability that pledges are received within 40 days
 
        
             
        
        
        
Answer:
120 times
Step-by-step explanation:
If we want to find a qunatity is how many times as other quantity, we have to divide the large one by the small one (remember, same units).
Let's make both into inches.
We have 1 inch [model]
also
10 feet * 12 = 120 inches
Thus, we can say:
120/1 = 120 times
So, Actual Plane is 120 times than model airplane
 
        
             
        
        
        
It is about 41.4% according to my TI-83/84 calculator.
 
        
        
        
Answer:   888+88+8+8+8 = 1,000
Step-by-step explanation: First of all line all your eights' up and then split them