Writing an equation is the easiest way to figure this out.
b = boys, g = girlsb = 3/4g35 students = g + b35 = g + 3/4g35 = 7/4g35/7/4 = g20 girls35 - 20 = b or 3/4(35) = b15 boys
Answer:
66 ≤ f ≤100
Explanation
Mean= ( Σ x ) / n
Mean= sum of scores/ number of subject she took
Now, she already too 3 subject which sum is 85+83+86=254
Now we need to know range of score for her to have (grade) a mark between 80 and 89
Now let take the lower limit mean=80
The lowest score she can get is
Mean = ( Σx) / n
80=(85+83+86+f)/4
80×4= 254+f
Therefore, f= 320-254=66
Therefore the minimum score she can have to have a B is 66.
Then, let take the upper limit mean 89. i.e the maximum she can have so that she don't have an A grade.
Mean = ( Σx) / n
89=( 83+85+86+f)/4
89×4= 254+f
f= 356-254
f=102.
Therefore this shows that she cannot have an A grade in the exam. The maximum score for the exam is 100.
There the range of score is 66 ≤ f ≤100 to have a B grade
66 ≤ f ≤100 answer
Since she cannot score 102 in the examination.
Volume of rectangle prism = w l h
Volume of rectangle pyramid = 1/3(w l h)
so Volume of rectangle pyramid = 1/3 (Volume of rectangle prism)
= 1/3 (240)
= 80
Answer:
80 cm^3
4. 55 + 0.65*55 = $90.75
5. 90.75 * 0.25*90.75 = $113.44
6. 113.44 - 0.33*113.44 = $76.00
