<u>Part a)</u> if a page is reduced to 80%, what percent enlargement is needed to return it to its original size?
Let
x---------> the percent enlargement
we know that
the original size is the 100%
so
x*80%=100%
x=(100%/80%)
x=1.25--------> 1.25=(125/100)=125%
therefore
<u>the answer Part a) is</u>
the percent enlargement is 125%
<u>Part b)</u> Estimate the number of times in succession that a page must be copied to make the final copy less than 15% of the size of the original
we know that
A photocopy machine can reduce copies to 80% of their original size
so
Copy N 1
0.80*100%=80%
Copy N 2
0.80*80%=64%
Copy N 3
0.80*64%=51.2%
Copy N 4
0.80*51.2%=40.96%
Copy N 5
0.80*40.96%=32.77%
Copy N 6
0.80*32.77%=26.21%
Copy N 7
0.80*26.21%=20.97%
Copy N 8
0.80*20.97%=16.78%
Copy N 9
0.80*16.78%=13.42%-------------> 13.42% < 15%
therefore
<u>the answer Part b) is</u>
the number of times in succession is 9
Answer:
There are 35 students in his class.
Step-by-step explanation:
1. Create a proportion: 60/100=21/x
2. Cross multiply, or not (I prefer to cross multiply). 60x=2100
3. Solve the equation: x=35.
Answer: There are 35 students in his class, 14 people going in school, 21 student online.
Answer:
a) 20%
b) 40%
c) Mean = 62.5 seconds; Variance = 52.083 seconds
Step-by-step explanation:
The time it takes a hematology cell counter to complete a test on a blood sample is continuously distributed over the period of 50 to 75 seconds with probability f(x) = 0.04.
a) The percentage of tests require more than 70 seconds is:
b)The percentage of tests that require less than one minute (60 seconds) is:
c) The mean and variance of a continuous distribution are determined by:
Mean = 62.5 seconds.
Variance = 52.083 seconds.
This is a combinations problem.
The total number of possible 2-item combinations is (1000 choose 2)
The number of 2-defective combinations is (300 choose 2)
The probability =
5c+10a=3570
c+a=512
...
a=512-c
so ...
5c + 10(512-c)=3570
