Answer:
The first is 30
Step-by-step explanation:
The third is 115
Ratio is 5girls:7boys with total 72 students
5+7= 12
72➗12= 6
6(5:7)= 30 girls : 42 boys
New ratio is 3:4 with 48 boys
48➗4= 12
So for girls 3x12= 36
So started with 30 girls ended with 36 girls... 6 girls joined band during the school year.
To divide fractions, you need to multiply by the reciprocal. The reciprocal of 3/4 is 4/3, which is why the work is incorrect.
See attached:
Answer:
To find the volume, we must find the area of the circle and multiply it by its height, think of a cylinder as an object made up of MANY circles. So, V=pir^2h... so diameter is 6cm so radius = 3cm...
therefore, Volume = (pi)(3^2)(12) = 108(pi)
where 12 = height 3 = radius
For the surface area, we need to find the area of the 2 circles(top and bottom ) so once again,
2(pi)(r^2) = 2(pi)(9)
for the area of the rectangle(if we unfold the cylindrical can) we get D(pi)(12) where D= Diameter
so the surface area is
SA = (2)(9)(pi) + 6(pi)(12)
SA = 18pi + 72pi = 90pi
Answer:
12
Step-by-step explanation:
