Answer:
Step-by-step explanation:
<u>We know that:</u>
<u>Let's first solve for y by choosing any equation.</u>
- 4x + y = 14
- => y = 14 - 4x
<u>Now, let's substitute the value of y into the second equation.</u>
- 6x - 3y = 3
- => 6x - 3(14 - 4x) = 3
- => 6x - 42 + 12x = 3
- => 18x - 42 = 3
- => 18x = 42 + 3
- => 18x = 45
- => x = 45/18 = 5/2 = 2.5
<u>Now, let's substitute the value of x into the equation of y.</u>
- => 14 - 4x = y
- => 14 - 4(2.5) = y
- => 14 - 10 = y
- => y = 4
Hence, the value of x and y are 2.5 and 4 respectively.
F(x) = 5x
for f(7) you replace x with 7 so it will be : f(7) = 5(7) = 35
Answer:
4.50 per melon
Step-by-step explanation:
Take the price and divide by the number of melons
13.50/3
4.50 per melon
Answer:
90 minutes or an hour and a half
Step-by-step explanation:
You need to find out how many minutes it takes her to run one mile, to do that you devide 54 by 6 and you get 9 minutes. Then you multiply the number of minutes per mile, 9, by 10 and you get 90 minutes.
Answer:
78.383%
Step-by-step explanation:
The pH of randomly selected swimming pools follows a normal distribution with mean 7.4 and standard deviation 0.22. A pool should have a pH between 7.2 and 7.8 so that chlorine treatment is effective.
Using z score formula
z = (x-μ)/σ, where
x is the raw score
μ is the population mean
σ is the population standard deviation.
For x = 7.2
z = 7.2 - 7.4/0.22
z = -0.90909
Probability value from Z-Table:
P(x = 7.2) = 0.18165
For x = 7.8
z = 7.8 - 7.4/0.22
z = 1.81818
Probability alue from Z-Table:
P(x = 7.8) = 0.96548
The probability of pools having an acceptable pH level(7.2 and 7.8)
= P(x = 7.8) - P(x = 7.2)
= 0.96548 - 0.18165
= 0.78383
Converting to percentage
0.78383 × 100
= 78.383%
The percentage of pools having an acceptable pH level is 78.383%
