Answer:
12
Step-by-step explanation:
x = number of $1 bills
y = number of $5 bills
z = number of $10 bills
We know that:
x + y + z = 25 (total amount of bills)
x + 5y + 10z = 100 (total amount of money)
y = 4z (Given)
Substitute the third equation into the first one.
x + 4z + z = 25
x = 25 - 5z
Put this into the second equation.
(25 - 5z) + 5 (4z) + 10z = 100
Simplify and solve.
25 - 5z + 20z + 10z = 100
25z + 25 = 100
25z = 75
z = 3
Substitute this into y = 4z
y = 4 * 3
y = 12
So, there are 12 $5 bills.
Answer:
109.33
Step-by-step explanation:
given that the population has a distribution with a mean of 110 and a standard deviation of 8
Sample size n = 40
Std error of sample mean = std dev/square root of sample size
= 
From std normal distribution table we find that 30th percentile for Z is
-0.5244
Corresponding x score =
30th percentile = 109.33663
=109.33
Answer:
20% psyche test scores
Step-by-step explanation:
Given that every week, Bob plays the guitar for three hours, and his grade on each psych test is 75 percent.
Last week, after playing for three hours, Bob considered playing for an additional hour.
He decided to play for another hour and cut his study time by one hour, but last week his psych grade was 55 percent.
Bob's opportunity cost of the fourth hour of playing the guitar
=His cut in scores in psyche test
=20%
Answer:
x=5
Step-by-step explanation:
-5(-x - 1) + 4x – 1= 49
Distribute
5x +5 +4x -1 = 49
Combine like terms
9x +4 = 49
Subtract 4 from each side
9x+4-4 = 49-4
9x = 45
Divide by 9
9x/9 =45/9
x = 5
