There is a chance of 1/16*1/15 that she gets the specific socks pair according to laws of probability and the counting principle but thats not how it will work over here.
As we should be guaranteed that she gets the number of socks she obviously must take out around 9 socks as we are taking the worst case scenario where all the socks that come out are the different ones so the ninth sock must match any of the others.
But if we draw three socks obviously the probability is 1/16*1/15*13/14 as we dont want the third one to be same. We can multiply the answer by 3 as it can be in three different orders.
Aruthmetic sequene is
an=a1+(n-1)d
where d=common difference between terms
adds 6 every time
d=6
first term is 8
a1=8
8+6(n-1)
distribute
8+6n-6
8-6+6n
2+6n is answer
Answer:
20 mph
Step-by-step explanation:
Let speed of Train a = Va mph
Let speed of Train b = Vb mph
Va = Vb + 30
Let time taken for Train a = Ta
Let time taken for Train b = Tb
time taken = distance travelled/speed
Ta = 350/Va = 350/(Vb+30)
Tb = 140/Vb
But they both travel in the same amount of time.
So, Ta = Tb
Cross multiply
Divide both sides by 210
10
A composite number is a positive integer. which is not prime (i.e., which has factors other than 1 and itself). The first few composite numbers (sometimes called "composites" for short) are 4, 6, 8, 9, 10, 12, 14, 15, 16, ... (OEIS A002808), whose prime decompositions are summarized in the following table.
