Associative property of mulipication, the ability to move parenthasees with mltipication or additon
Answer:
Let the speed of the train be x km/h.
Case 1:
Distance = 288 km
Speed = x km/h
Time = Distance/Speed
= 288/x h
Case 2:
Distance = 288 km
Speed = (x+4) km/h
Time = 288/x + 4 h
Since 288/x > 288/x + 4
288/x - 288/x+4 = 1
288[1/x - 1/x+4 ] = 1
[ x + 4 - x / x(x + 4) ] = 1/288
[4 / x^2 + 4x ] = 1/288
x^2 + 4x = 1152
x^2 + 4x - 1152 = 0
x^2 + 36x - 32x - 1152 = 0
x(x + 36) - 32(x + 36) = 0
(x + 36)(x - 32) = 0
x + 36 = 0 , x - 32 = 0
x = -36 , x = 32
x = -36 , rejected since speed cannot be negative.
Therefore , speed of the train = 32 km/h
<span>For more difficult cases, it may be easier to draw the graph first using the domain if possible and then determine the range graphically.See if you can find the inverse function. The domain of a function's inverse function is equal to that function's range.<span>Check to see if the function repeats.</span></span>
Answer:
The probability that they purchased a green or a gray sweater is 
Step-by-step explanation:
Probability is the greater or lesser possibility of a certain event occurring. In other words, probability establishes a relationship between the number of favorable events and the total number of possible events. Then, the probability of any event A is defined as the quotient between the number of favorable cases (number of cases in which event A may or may not occur) and the total number of possible cases. This is called Laplace's Law.

The addition rule is used when you want to know the probability that 2 or more events will occur. The addition rule or addition rule states that if we have an event A and an event B, the probability of event A or event B occurring is calculated as follows:
P(A∪B)= P(A) + P(B) - P(A∩B)
Where:
P (A): probability of event A occurring.
P (B): probability that event B occurs.
P (A⋃B): probability that event A or event B occurs.
P (A⋂B): probability of event A and event B occurring at the same time.
Mutually exclusive events are things that cannot happen at the same time. Then P (A⋂B) = 0. So, P(A∪B)= P(A) + P(B)
In this case, being:
- P(A)= the probability that they purchased a green sweater
- P(B)= the probability that they purchased a gray sweater
- Mutually exclusive events
You know:
- 8 purchased green sweaters
- 4 purchased gray sweaters
- number of possible cases= 12 + 8 + 4+ 7= 21
So:
Then:
P(A∪B)= P(A) + P(B)
P(A∪B)= 
P(A∪B)= 
<u><em>The probability that they purchased a green or a gray sweater is </em></u>
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1.Add the metal and wooden bats together
15+9=24
2. Create fraction
9/24
3.turn into a decimal by dividing numerator(top number) by denominator(bottom number).
9/24=0.375
4.multiply by 100 to get percentage
0.375*100=37.5
Therefore there is a 37.5 chance that he picks a metal bat