Answer:
There are 32 pupils in the class
Step-by-step explanation:
Let's say there are N pupils in the class. Then each pupil must send N-1 cards - because it would make no sense to send one to themselves! So each of the N pupils send N-1 cards, which becomes 992 cards in total. In equation form, this is
This is a second degree polynomial, which has the solutions
where
If we insert these numbers in the equation,
If we choose the solution with the minus sign, we get
N=-31
but this makes no sense! There can't be a negative number of pupils in the class!
So we choose the solution with the plus sign,
So there are 32 pupils in the class
Answer: 2 gallons
Step-by-step explanation: 8 pints= 1 gallon so 16 pints=2 gallons
Answer: 180 ft^2 is the area of bedroom 1
Step-by-step explanation:
15 * 12 = 180
Doors:
3 * 6.5 = 19.5
Windows: 3 * 4 = 12
Hope that helps
Answer: 1068
Step-by-step explanation:
Formula of sample size :
, where p = prior population proportion , E = margin of error , = Critical z- value.
Let p = proportion of visitors who are repeat visitors.
Given : p=0.5
E= 3%= 0.03
critical z-value for 95% confidence = 1.96
Now,
[round to the next integer]
Hence, the required sample size = 1068
Answer:
v= 141.37
Step-by-step explanation:
π · 3^2 · 15/ 3
=141.37167