Mumbai University > Mechanical Engineering > Sem 4 > Applied Mathematics IV

Marks: 5M

Year: Dec 2015

Expectation : E(X) = 4

Total counter in a bag = 10

Counter of Rs. 5 in a bag = 6

Let the four bag have a value of Rs. X

$\mathrm{\therefore }$ Counter of X Rs. In a bag = 10-6 = 4

Probability of drawing a single counter is 1/10

$\mathrm{\therefore }$ Probability of drawing 5 Rs. Counter is 6/10

$\mathrm{\therefore }$ Probability of drawing x Rs. Counter is 4x/10

$\mathrm{\therefore }$ Expectation : E(X) = $\sum{p_i.X_I}$

4 = 6/10 *(5) + (4/10) * x

$\mathrm{\therefore }$ 40 = 30+ 4x

$\mathrm{\therefore }$ 4x = 10

$\mathrm{\therefore }$ x =2.5

$\boldsymbol{\mathrm{\therefore }}$ Unknown value is Rs. 2.5