X = √7²+4² by using Pythagoras Theory as the triangle is a right angled triangle
Let's make a system of equations to solve for this:
n + q = 84
0.05n + 0.25q = 12.80
where n = nickels and q = quarters.
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Solve for n in the first equation by subtracting q from both sides.
n = 84 - q
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Plug n into the second equation.
0.05(84 - q) + 0.25q = 12.80
Distribute 0.05 inside the parentheses.
4.2 - 0.05q + 0.25q = 12.80
Combine like terms.
4.2 + 0.2q = 12.80
Subtract 4.2 from both sides.
0.2q = 8.6
Divide both sides by 0.2.
q = 43
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Plug 43 for q in the first equation.
n + (43) = 84
Subtract 43 from both sides.
n = 41
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There are 41 nickels and 43 quarters in the piggy bank. ✅
Answer:

Step-by-step explanation:

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For statictics of Out of 780 smokers, 376 have been divorced, Non-smokers: Out of 2855 non-smokers, 902 have been divorced, the 95% confidence interval for smokers and non-smokers is mathematically given as
- 95% confidence interval = (0.5352, 0.4462)
- 95% confidence interval = (0.3424, 0.2894)
- 53% increased risk of divorce for smokers.
<h3>What is the 95% confidence interval for smokers and non-smokers?</h3>
Generally, the equation for the Confidence interval is mathematically given as
p ± Z/2[p(1-p)]/n
Where
Z1/2=1-(0.05/2)
Z1/2=0.975
Read z table we have
Z score= 1.96
Hence
0.4907 ± 1.96 (0.4907)(1-0.4907)/485
0.4907±0.0445
Therefore
95% confidence interval = (0.5352, 0.4462)
b)
Z1/2 = 1- (0.05/2)
Z1/2 = 0.975
Z score= 1.96
0.3159 ± 1.96 (0.3159)(1-0.3159)/1184
0.3159±0.0265
Thereofore
95% confidence interval = (0.3424, 0.2894)
c)
In conclusion, The 95% confidence interval helps us read that 53% increased risk of divorce for smokers.
Read more about Confidence interval
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