Answer:
480,700 sets (first choice)
Step-by-step explanation:
If all 25 questions are different,
When order of selection counts:
P(25,7)
= 25!/(25-7)!
= 15511210043330985984000000/6402373705728000
= 2422728000
When order of selection does not count count:
C(25,7)
=25!/(7!*(25-7)!)
=15511210043330985984000000/(6402373705728000*5040)
= 480,700
Hope this helps, have a nice day.
Considering there is a function (relationship) and that it is linear, the distance will change proportionally to time constantly. In other words, we are taking the speed to be constant throughout the journey.
If we let:
t = time (min's) driving
d = distance (miles) from destination
Then we can represent the above information as:
t = 40: d = 59
t = 52: d = 50
If we think of this as a graph, we can think of the x-axis representing time and the y-axis representing the distance to the destination. Being linear, the function will be a line, i.e. it will have a constant gradient. If you were plot the two points inferred from the information and connect the two dots, you will get a declining line (one with a negative gradient) representing the inversely proportional relationship or equally, the negative correlation between the time driving and the distance to the destination. The equation of this line will be the linear function that relates time and the distance to the destination. To find this linear function, we do as follows:
Find the gradient (m) of the line:
m = Δy/Δx
In this case, the x-values are t-values and our y-values are d-values, so:
Δy = Δd
= 50 - 59
= -9
Δx = Δt
= 52 - 40
= 12
m = -9/12 = -3/4
Note: m is equivalent to speed with units: d/t
Use formula to find function and rearrange to give it in the desired format:
y - y₁ = m(x - x₁)
d - 50 = -3/4(t - 52)
4d - 200 = -3t + 156
4d + 3t - 356 = 0
Let t = 70 to find d at the time:
4d + 3(70) - 356 = 0
4d + 210 - 356 = 0
4d - 146 = 0
4d = 146
d = 73/2 = 36.5 miles
So after 70 min's of driving, Dale will be 36.5 miles from his destination.
The correct answer is D. 36 x 1/9
When there is a negative exponent on a whole number:
4 ^-2
1/ 4 ^2 = 1b16
<h3>
Answer: D) 144 square cm</h3>
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Explanation:
A square has all four sides that are the same length. So all four sides are 12 cm
area = side*side = 12*12 = 144 cm^2
Or you could say
area = (side)^2 = (12)^2 = 144 cm^2
Squaring a number is the same as multiplying it by itself. Hence the name "square" refers to a side length pairing up with its corresponding area value.
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Side note: The perimeter is 4*(side) = 4*12 = 48 cm. It's possible that choice B is put in there as a trick answer.
