Answer:
12 (i think)
Step-by-step explanation:
so you see the problem the first problem is 3x-9. and you see 27
then you multiply 12 by 3 and you get 36 then you minus 36 by 9 and you get 27
Answer:
D. 48
Step-by-step explanation:
Let's first find the probability that in the first 40 trials, exactly two of the coins are heads.
We know that there were 16 such outcomes of 2 heads and 1 tail, and there was a total of 40 possible outcomes. So our probability is:
16 / 40 = 4 / 10 = 2/5
We can assume that the probability that in the next 120 trials, about 2/5 of the outcomes will also be 2 heads and 1 tail. So, we multiply 2/5 by 120 to figure out that exact number:
(2/5) * 120 = 240/5 = 48
The answer is thus D.
Let D = the amount of money Deanna has after x games.
We know Deanna started with $15 and she spends 0.75 per game, so we can make the following equation:
D = 15 - 0.75x
Let L = the amount of money Lisa has after x games.
We know Lisa started with $13 and she spends 0.50 per game, so we can make the following equation:
L = 13 - 0.5x
The question is asking how many games need to be played for L and D to be equal, so just equate L and D and solve for x:
D = L
15 - 0.75x = 13 - 0.5x
15 - 13 = -0.5x + 0.75x
2 = 0.25x
2 = (1/4)x
8 = x
Therefore they need to play 8 games each to have the same amount of money.
28 out of 40 of the students passed the test
