When it is greater than 9.
Example
15
x 5
——-
5x5 is 25, so you would leave 5 and carry the 2
2
15
x. 5
——-
5
A=4h BECAUSEE 2 times 4 is 8 and 5 times 4 is 20 caught the pattern yet? it's multiplying
The answer for this problem is 43
Prob ( guessing right) = 0.25 . Get 1 point.
Prob( guessing wrong) = 0.75. Lose 0.5 points.
Expected value = 1(0.25) + (-0.5)(0.75)
= -0.125 answer