Answer:
C.
Step-by-step explanation:
❌Option A is incorrect
Rationale: from the graph, 1 hr on the x-axis doesn't correspond to $100 on the y-axis
❌Option B is incorrect
Rationale: from the graph, 2 hrs on the x-axis doesn't correspond to $200 on the y-axis. It can't also be the unit rate because unit rate would be the amount of dollars per 1 hr.
✅Option C is CORRECT
Rationale: from the graph, 8 hrs on the x-axis corresponds to $500 on the y-axis
❌Option D is incorrect
Rationale: from the graph, 4 hr on the x-axis doesn't correspond to $300 on the y-axis
Answer:
-1.75.
Step-by-step explanation:
The z-score = (n - m) / d where n is the value (13) m = mean and d = standard deviation.
= (13 - 20) / 4
= -1.75 (answer)
Step One
Find z
All triangles have 180 degrees. No exceptions.
z + 47 + 90 = 180 combine like terms on the left.
z + 137 = 180 subtract 137 from both sides
z = 180 - 137
z = 43 degrees.
Step Two
Use the sine function to find y
Sin(43) = opposite side / hypotenuse
opposite side = 35
sin(43) = 35 / hypotenuse
hypotenuse = 35 / sin(43)
y = 35/0.6820
y = 51.32
Solve using cos(x)
Note this problem could have been done in a shorter way.
Cos(47) = adjacent / hypotenuse.
hypotenuse = adjacent / cos(47)
y = 35 / cos(47)
y = 35 / 0.6820
y = 51.32 Both answers agree. It is a good thing to know how to do this question both ways.
Answer:
1. 
2. 
Step-by-step explanation:
Let the number of people in the group be x. Denote the total cost as C.
1. If the regular cost is $21 per person, then the total regular cost for x people is 
2. If the special cost is $8 per person, then the total special cost for x people is
There is an additional $104 fee for a private room, thus the total special cost is 
a) 9 toilet rolls cost $ 4.23
1 toilet roll costs $ x
9x = 4.23 * 1
x= 4.23 / 9
x = 0.47
So in first case one toilet roll costs $ 0.47.
b) 4 toilet rolls cost $1.96
1 toilet roll costs $ x
4x = 1.96 * 1
x = 1.96 / 4
x = 0.49
So in second case one toilet roll costs $ 0.49.
0.47 < 0.49
The toilet roll in first case is cheaper than the toilet roll in second case.
Hope this heps!