My Mom did the work. The answer came out as X= 4.
Answer:
P(XX) = 69/190
Step-by-step explanation:
Given:
20 balls, 10R, 3B, 7W.
Two taken without replacement.
Find probability of two identical colours.
P(XX)
Solution:
We use the multiplication rule for the probability of each of the 2 draws
P(RR) = 10/20*9/19 = 90/380
P(BB) = 3/20*2/19 = 6/380
P(WW) = 7/20*6/19 = 42/380
Probability of drawing two identical coloured balls
P(XX) = (90+6+42)/380 = 138/380 = 69/190
V1=50km/h
v2=90km/h
s1=s2=6km
s=12km
The average speed over the 12 km drive:
v=s/t
The time needed to drive 12km will be:
t = t1+t2
t1=s1/v1, t2=s2/v2
t=s1/v1+s2/v2=(s1v2+s2v1)/(v1v2)
v=sv1v2/(s1v2+s2v1)=12*50*90/(6*50+6*90)=64,28 km/h
Answer:
26
Step-by-step explanation:
Multiple by 65 by 40% or 0.4 and you get 26 .
