So we know that surface area is top circle +bottom circle+ (circumfurence times height so) 2(π(radius)^2)+(height(2π(r))) so fill in the blanks
it's kind of hard to see but πr means pi times radius (r)
2πr^2+((4.2)(2)(π)(r))=628.3
factor out the 2 so the equation would mean
2((πr^2)+(4.2πr))=628.3
divide both sides by 2
πr^2+4.2πr=314.15
what's interesting is that the first few digits of pi are 3.1415 so we aproximate pi as 3.14 and divide both sides by 3.1415
r^2+4.2r=100
subtract 100 from both sides
r^2+4.2r-100=0
factor
(x-8.11812)(x+12.3181)=0
so (if xy=0 then x or/and y must be 0 so)we set them to 0 so
x-8.11812=0
x=8.11812
second one
x+12.3181=0
x=-12.3181
since radii (or any legnth) cannot be negative, we can cross this solution out so
radius=8.11812
The total possibilities can be 756 ways.
<h3>What is combination?</h3>
A combination is a mathematical technique that determines the number of possible arrangements in a collection of items where the order of the selection does not matter. In combinations, you can select the items in any order. Combinations can be confused with permutations.
Given:
The number of ways in which we can select atleast 3 men in the committee are 756.
Number of men = 7
Number of women = 6
Number of people that should be selected in the committee = 5
Now,
N(M = 3) = 7C_3* 6C_2
=35*15
=525
N(M = 4) = 7C_4* 6C_1
=35*6
=210
N(M = 3) = 7C_5* 6C_0
=21*1
=21
So, total possibilities can be = 525 + 210 + 21 = 756 ways.
learn more about combination here:
brainly.com/question/28390900
#SPJ4
Answer:
second one
Step-by-step explanation:
The width is basically the diameter:
Given
Diameter = 5.5 cm
So Radius =

=

= 2.75 cm
Height of cylinder = 12.5 cm
Formula of the volume of a cylinder
V = Area of base × height of prism
=

r² × h
=(2.75)² (

) × 12.5
=7.5625

× 12.5
≈ 296.83 cm³
Its blurry cant see anything reallly