Answer:
x=70
Step-by-step explanation:
To solve this problem, you set up the equation 45+(2x-5)=180
Next, subtract 45 from 180 to get the equation 2x-5=135
After that, add 5 to 135 to get 2x=140
Divide 140 by 2 to get X=70
Answer: n = 75; p = 30
Explanation: (a) 5p + 4n = 450 where p is for pen and n is for notebook.
(b) 10p + 3n = 525
We can use the elimination method to solve these two equations.
1. Multiply the first equation by 2 so that 10p will cancel out:
2(5p + 4n = 450)
- 10p + 3p = 525
10p + 8n = 900
- 10 p + 3n = 525
5n = 375
2. Divide by 5 to get n alone: n = 75
3. Plug 75 into the first equation: 5p + 4(75) = 450
5p + 300 = 450
4. Subtract 300 from 450: 5p = 150
5. Divide by 5 to get p alone: p = 30
We can test if this is correct by plugging our answers into the second equation:
10(30) + 3(75) = 525
300 + 225 = 525
525 = 525
This is a true statement, which means that our answers are correct.
Answer:
0.61596
Step-by-step explanation:
Given that:
λ = 5 (5 errors per page)
Poisson distribution formula :
P(x = x) = (λ^x * e^-λ) / x!
Probability that page does not need to be retyped means that error on page is less than or equal to 5
P(x ≤ 5) = p(x = 5) + p(x = 4) +... + p(x = 0)
The individual probabilities can be obtained using the formula above or the use of a calculator
P(x ≤ 5) = 0.17547 + 0.17547 + 0.14037 + 0.08422 + 0.03369 + 0.00674
P(x ≤ 5) = 0.61596