In a multiple choice question the probability of success is : p = 1/4 = 0.25
and the probability of failure is : q = 3/4 =) 0.75
r = 7 ( correct answers )
Probability = 10 C r * ( 1/4 ) ^(10- r) * ˙( 3/4 )^r =
= 10 C 7 * ( 0.25 )^3 * ( 0.75 )^7 =
= 120* 0,00208568572 =
= 0,2502822864
Answer: Probability is 0,2502822864 or 25.02822864 %.