Answer:
The number of bacteria after 
will be 
Step-by-step explanation:
Given the initially 30 bacteria present in the culture.
Also, the number of bacteria got doubled every hour.
So, using the equation
Where 
is number of bacteria after 
hours.
is bacteria present initially.
is the common ration, in our problem it is given that bacteria doubles every hour. So, 
And is the number of hours. In our problem we need amount of bacteria at the end of hours. So, 
Plugging values in the formula we get,
So, number of bacteria after will be
Answer:
D
Step-by-step explanation:
Short Answer: y = 36°
Remark
What an interesting question!! The first thing you have to do is find out what the interior angle of a regular pentagon is. After you have done that, you can calculate y.
Method.
The exterior angles of a regular figure add up to 360°.
Step One
Find out the size of the exterior angles of a regular pentagon.
There are 5 such angles. They add up to 360°
5x = 360 Divide by 5
x = 360 / 5
x = 72°
Step Two
Find out the value of the interior angles of a pentagon.
Method
The interior and exterior angles add up to 180°
Exterior Angle + Interior Angle = 180°
Exterior angle = 72 degrees
72° + Interior Angle = 180° Subtract 72 from both sides.
Interior Angle = 180° - 72°
Interior Angle = 108°
Step Three
Solve for y.
There are 3 tiles each with an angle of 108° that are placed together. So y + 3 interior angles = 360°
y + 3*interior angles = 360°
y + 3*108 = 360
y + 324 = 360 Subtract 324 from both sides.
y = 360 - 324
y = 36°
Average of 2 numbers is 40
so total = 2 x 40 = 80
300 - 80 = 220
average of remaining 10 numbers = 220/10 = 22
answer
B) 22
