Answer:
90
Step-by-step explanation:
There are 10 people who can be picked for the first position, which leaves 9 people who can be picked for the second position.
10 × 9 = 90
You can also use permutations.
₁₀P₂ = 90
Answer:
18 days.
Step-by-step explanation:
We have been given that 12 painters paint the wall of a school in 21 days.
So the wall painted by one painter will paint the wall in
As one painter will paint the wall in 252 days, so to find the number of days it will take to paint the same wall by 14 painters, we will divide time taken by one painter (252) by 14.


Therefore, it will take 18 days to paint the same wall by 14 painters.
In this case we have the following trinomial:

By definition, the factorization is a technique that consists in the mathematical decomposition of an expression, in the form of a product. Having said that, we can factor the given trinomial in the following way:
We look for two numbers that when multiplied give as result 42, and when summed give as result -13.
The numbers that meet these two conditions are -6 and -7 by:

So, we have:

Answer:
The binomials associated with the given trinomial are
and
.
The given data is
Scores: 90-99 80-89 70-79 60-69 50-59
Students: 3 7 12 4 4
Because we are to take the middle value for each group.
Therefore the total score is
Sx = 3*94.5 + 7*84.5 + 12*74.5 + 4*64.5 + 4*54.5 = 2245
The number of students is 3+7+12+4+4 = 30
The mean is
m =2245/30 = 74.833
Calculate (Sx - m)²
(Sx - m)² = 3*(94.5-74.833)² + 7*(84.5-74.833)² + 12*(64.5-74.833)²
+ 4*(64.5-74.833)² + 4*(54.5-74.833)² = 3896.7
Calculate the standard deviation
s = √(3896.7/29) = 11.592
Answer:
mean = 74.83
std. deviation = 11.59