The last 2 options are correct
Answer:
DE = 15
DF = 23
Step-by-step explanation:
E___D___F
EF = DE + DF
38 = (3x +9) + (12x-1)
38 = 15x + 8
15x = 38 - 8
15x = 30
x = 30/15
x = 2
DE = 3x + 9 = 3(2) + 9 = 6 + 9 = 15
DF = 12x - 1 = 12(2) - 1 = 24 - 1 = 23
I hope I helped you^_^
We have the formula to compute the probability of having exactly k successed over n trials, given a probability p of success (and implicitly a probability 1-p of failure), which is

Now, the probability of at least 3 successes is the union of the following event: exactly three successes,exactly four successes and exactly five successes.
We can compute their probability and sum them:
So, the answer is about 36.79%
You can make 5 prisms and one extra unit left
<span>6+2(4v-5)=-2(7v-4)+7v
</span><span>6 + 8v - 10 = -14v + 8 +7v
8v - 4 = -7v + 8
15v = 12
v = 12/15
v = 4/5</span>