Answer:
5 chaperones are needed.
Step-by-step explanation:
400 x 4/5 = 320
320 ÷ 75 = 4.3
Answer:
162
Step-by-step explanation:
( -a ) ( b ) ( -a + b )
-6 ( 3 ) ( -6 + -3 )
-6 ( 3 ) ( -9 )
- 18 ( -9 )
162
A, B and C working together will finish same piece of work in 10 days
A can do a piece of work in 20 days. That is A is doing the work at a rate of 1 / 20. Therefore
B = 1 / 30
C = 1 / 60
A, B and C working togehter their rate will be added together =
A + B + C = 1 / 20 + 1 / 30 + 1 / 60 = 1 / 10
so they can work together to finish same piece of work in 10 days
Answer:

Step-by-step explanation:
Given
sinΘ =
= 
Then the hypotenuse = 5 and one leg of the right triangle is 3
Using Pythagoras' identity to find the second leg (x)
x² + 3² = 5²
x² + 9 = 25 ( subtract 9 from both sides )
x² = 16 ⇒ x = 4
cosΘ =
= 
Answer:
The 90% confidence interval for population mean is 
Step-by-step explanation:
From the question we are told that
The sample mean is 
The confidence level is 
The sample size is 
The standard deviation
Now given that the confidence level is 0.90 the level of significance is mathematically evaluated as


Next we obtain the critical value of
from the standardized normal distribution table. The values is 
The reason we are obtaining critical values for
instead of that of
is because
represents the area under the normal curve where the confidence level 1 -
(90%) did not cover which include both the left and right tail while
is just considering the area of one tail which is what we required calculate the margin of error
Generally the margin of error is mathematically evaluated as

substituting values


The 90% confidence level interval is mathematically represented as

substituting values


