Answer: $17.92/sandwich
Step-by-step explanation:
Let S be the price of a sandwich ($/sandwich).
7S is the total cost of the sandwiches. Add a drink for $2.50 to find the total cost, which we are told comes to $140.50
7S + $2.50 = $140.50
7S = $138
S = $19.7143
It is odd that this includes a fraction of a single penny (0.43 cents). Something is incorrect in the data given, since this should equal a whole number. For now, I'll round up to $19.72. The additional 7*($0.0043) = 4 cents will be treated as a tip.
Answer:
The variation rate is 4.07 × 10⁻⁵ cm²/ºC
Step-by-step explanation:
The relationship of the change in length as a function of the temperature, which are given in this problem can be written by the expression for the area of a rectangle
a = L × W
Differentiating both sides,
= 
= W
+ L 
The values they give us are
= 1.1 × 10⁻⁵ cm/ºC
= 8.9 × 10⁻⁶ cm/ºC
W = 1.6 cm
L= 2.6 cm
Substituting the values and calculating
= (1.6 × 1.1 × 10⁻⁵) + (2.6 × 8.9 × 10⁻⁶)
= (1.76 × 10⁻⁵) + (2.31 × 10⁻⁵)
= 4.07 × 10⁻⁵ cm²/ºC
The variation rate is 4.07 × 10⁻⁵ cm²/ºC
Answer:
a
Step-by-step explanation:
Answer:
99% CI: [45.60; 58.00]min
Step-by-step explanation:
Hello!
Your study variable is:
X: Time a customer stays in a certain restaurant. (min)
X~N(μ; σ²)
The population standard distribution is σ= 17 min
Sample n= 50
Sample mean X[bar]= 51.8 min
Sample standard deviation S= 27.68
You are asked to construct a 99% Confidence Interval. Since the variable has a normal distribution and the population variance is known, the statistic to use is the standard normal Z. The formula to construct the interval is:
X[bar] ±
*(σ/√n)

Upper level: 51.8 - 2.58*(17/√50) = 45.5972 ≅ 45.60 min
Lower level: 51.8 + 2.58*(17/√50) = 58.0027 ≅58.00 min
With a confidence level of 99%, you'd expect that the interval [45.60; 58.00]min will contain the true value of the average time customers spend in a certain restaurant.
I hope you have a SUPER day!
PS: Missing Data in the attached files.
The answer is Y=7/2x. If you need more help ask