Answer:
the probability is 78.4%
Explanation:
there are 3 scenarios
1) gets the price in the 1st box:
the probability is:
P = probability to obtain a price = 4/10= 40%
2) gets the price in the 2nd box
P= probability to fail in the fist box * probability to obtain a price
P= (6/10)*(4/10)=24/100 = 24%
3) gets the price in the 3rd box
P =probability to fail in the first box * probability to fail in the second box*probability to obtain a price =(6/10)*(6/10)*(4/10)=144/1000 = 14,4%
therefore the probability to obtain a price in 3 or less boxes is:
P = 40%+24%+14.4%= 78.4%