Answer:
195.25
Step-by-step explanation:
Consider geometric series S(n) where initial term is a
So S(n)=a+ar^1+...ar^n
Factor out a
S(n)=a(1+r+r^2...+r^n)
Multiply by r
S(n)r=a(r+r^2+r^3...+r^n+r^n+1)
Subtract S(n) from S(n)r
Note that only 1 and rn^1 remain.
S(n)r-S(n)=a(r^n+1 -1)
Factor out S(n)
S(n)(r-1)=a(r^n+1 -1)
The formula now shows S(n)=a(r^n+1 -1)/(r-1)
Now use the formula for the problem
<u>8th Grade: </u>90 x 0.80 = 72
<u>7th Grade:</u> 80 x 0.75 = 60
Conclusion: 8th Graders like pop music more because 72 out of the 90 in 8th grade Dave surveyed enjoy it, compared to the 60 out of 80 in 7th grade that enjoyed it.
Answer:
<u><em>90 males.</em></u>
Step-by-step explanation:
To find the answer we will <u><em>divide 45% by 100</em></u>, and we get <u><em>0.45</em></u>. Now <u><em>multiply 0.45 by 200</em></u> and you get <u><em>90</em></u>. Therefore, <u><em>90 males is the answer. </em></u>
I think that 30 bulbs are expected to be defective.