Can u solve this Math question?
"A" speaks truth in 75% cases n "B" in 80% cases.In what % of cases are they likely to contradict each other,narrating the same incident? a)5% b)15% c)35% d)45% The ans is 35% can anyone explain how n why??
- Anonymous9 years agoFavorite Answer
The way I read it, you want the probability of them contradicting each other. This can occurs in two ways, either
A.)Person A tells the truth (75% chance) and B lies (20% chance)
B.)Person A lies (25% chance) and person B tells the truth (80% chance)
To find the total chance, you find the chance of either of those events occurring then add them together. So,
Chance of event A occurring=.75*.20=.15
Chance of event B occurring=.25*.8=.2
So added together, Chance A+Chance B=.35 or 35%. Does that make sense?
- 9 years ago
If A speaks the truth, there is a 15% chance B will be contradicting because 3/4 * 1/5 = 3/20 = 15%
If B speaks the truth, there is a 20% chance A will be contradicting because 4/5 * 1/4 = 4/20 = 20%
15 + 20 = 35%
- 9 years ago
Here is what i think:
for them to contradict each other either A says a truth and B lies or A lies and B says a truth.
For the first case (A truth, B lie) , the probability is:
For the second case (A lie, B truth):
So there is a 15% chance of case 1 and a 20% chance of case 2. But you want to know the total:
This is what I would think just using logic.