JAMB - Mathematics (2008 - No. 45)
The result of rolling a fair die 150 times is as summarized in the table above. What is the probability of obtaining a 5?
3/10
1/5
1/6
1/10
Explanation
Total possible outcome
12+18+x+30+2x+45 = 105+3x
∴105+3x = 150
3x = 150-105
3x = 45
x = 15
P(obtaining 5) = \(\frac{2x}{(105+3x)}But x= 15\)
=\(\frac{2(15)}{(105+3(15))}\)
=\(\frac{30}{(105+45)}\)
=\(\frac{30}{150}\)
=\(\frac{1}{5}\)
12+18+x+30+2x+45 = 105+3x
∴105+3x = 150
3x = 150-105
3x = 45
x = 15
P(obtaining 5) = \(\frac{2x}{(105+3x)}But x= 15\)
=\(\frac{2(15)}{(105+3(15))}\)
=\(\frac{30}{(105+45)}\)
=\(\frac{30}{150}\)
=\(\frac{1}{5}\)
Comments (0)
