Answer:
Step-by-step explanation:
Confidence interval for the difference in the two proportions is written as
Difference in sample proportions ± margin of error
Sample proportion, p= x/n
Where x = number of success
n = number of samples
For the men,
x = 318
n1 = 520
p1 = 318/520 = 0.61
For the women
x = 379
n2 = 460
p2 = 379/460 = 0.82
Margin of error = z√[p1(1 - p1)/n1 + p2(1 - p2)/n2]
To determine the z score, we subtract the confidence level from 100% to get α
α = 1 - 0.95 = 0.05
α/2 = 0.05/2 = 0.025
This is the area in each tail. Since we want the area in the middle, it becomes
1 - 0.025 = 0.975
The z score corresponding to the area on the z table is 1.96. Thus, confidence level of 95% is 1.96
Margin of error = 1.96 × √[0.61(1 - 0.61)/520 + 0.82(1 - 0.82)/460]
= 1.96 × √0.0004575 + 0.00032086957)
= 0.055
Confidence interval = 0.61 - 0.82 ± 0.055
= - 0.21 ± 0.055
Answer:
x + (5x-9)
Step-by-step explanation:
x stands for the number of coins Nancy has
Kevin has 9 less than 5 times what Nancy has, so his part of the expression is 5x-9
To find the total number of coins they have, you have to add Nancy's number of coins x plus Kevin's number of coins 5x-9
x + (5x-9)
But you have to put parentheses around Kevin's 5x-9 so that part of the expression is calculated first, as per order of operations
Answer:
Exact Form: 15/2
Decimal Form: 7.5
Mixed Number Form: 7 1/2
Step-by-step explanation:
Answer 1 3/5 × 40=64
Step-by-step explanation:
4×2/5=1 3/5 4×10=40
