Answer:
A salad costs $2.50
A sandwich costs $4.50
A drink costs $1.25
Step-by-step explanation:
Let x represent the salad, y represent the sandwich, and z represent the drink.
Since three salads, two sandwiches, and one drink cost $17.75:
3x + 2y + z = 17.75 (1)
Since one salad, one sandwich, and three drinks cost $10.75:
x + y + 3z = 10.75 (2)
Since a salad costs twice as much as a drink:
x = 2z (3)
Multiply the equation 2 by -2 then, sum the equation 1 and equation 2:
-2x - 2y - 6z = -21.50
3x + 2y + z = 17.75
→ x - 5z = -3.75
Replace the x with 2z using equation 3:
2z - 5z = -3.75
-3z = -3.75
z = 1.25
x = 2z → x = 2.50
x + y + 3z = 10.75 → 2.50 + y + 3.75 = 10.75 → y + 6.25 = 10.75 → y = 4.50
Answer:
a. The percentage of vehicles who pass through this construction zone who are exceeding the posted speed limit =90.82%
b. Percentage of vehicles travel through this construction zone with speeds between 50 mph and 55 mph= 2.28%
Step-by-step explanation:
We have to find
a) P(X>40)= 1- P(x=40)
Using the z statistic
Here
x= 40 mph
u= 44mph
σ= 3 mph
z=(40-44)/3=-1.33
From the z-table -1.67 = 0.9082
a) P(X>40)=
Probability exceeding the speed limit = 0.9082 = 90.82%
b) P(50<X<55)
Now
z1 = (50-44)/3 = 2
z2 = (55-44)/3= 3.67
Area for z>3.59 is almost equal to 1
From the z- table we get
P(55 < X < 60) = P((50-44)/3 < z < (55-44)/3)
= P(2 < z < 3.67)
= P(z<3.67) - P(z<2)
= 1 - 0.9772
= 0.0228
or 2.28%
Answer:
0/8
Step-by-step explanation: i tried my best
c. 35 + 50x ≤ 1,325
Step-by-step explanation:
Abbey's total cost must be less then or equal to her total savings, i.e.
cost ≤ savings
it is given that cost = fixed registration fee and a monthly fee of $50 per month. Hence,
fixed registration + (monthly fee)*(number of months) ≤ savings
let the number of months be x,
hence
35 + 50x ≤ 1325(c)
