8 total pens....4 are black
first pick, probability of being black is 4/8
2nd pick. without replacing, probability is 3/7
probability of a black pen picked first and then another black pen picked again is : 4/8 * 3/7 = 12/56 = 0.21
Yea I don’t know sorry bye
For this on you need to set up two equations
x + y = 155 total number of packages
3x+8y=815 total weight
Then multiply both sides of the first equation by 3: 3x +3y = 465
Then combine the two equations by subtracting the first one from the second one which gets you 5y=350 so y = 70 so we have 70 packages weighting 8 pounds.
Answer:
I might be wrong but I think this is the answer 10460353203
Step-by-step explanation:
Answer:

Step-by-step explanation:
Entrance fee per head = d
Entrance fee for the 5 friends = 5*d = 5d
Booklet of ride ticket per head = 2.5d
Booklet of ride ticket for the 5 friends = 5(2.5d)
Meal ticket per head = d - 4
Meal ticket for the 5 friends = 5(d - 4)
Total amount paid altogether by the five friends = 
From this breakdown above, the total amount paid by the 5 friends for their meal tickets = 