Amcat

Amcat-Q1:  The probability that a student passes Subject A, B or C is 98%. The probability that he or she passes A is 41%, B is 59%. The probability that he or she passes A and C is 25% and B and C is 20%. The probability that he or she passes all the 3 subjects is 14%. What is the probability that he or she passes subject C?

Ans. 29
P(AUBUC) = P(A)+P(B)+P(C)-P(AnB)-P(BnC)-P(AnC)+P(AnBnC)
98 = 41+59+c-0-20-25+14
c = 29

Amcat-Q2:   Ritu has 3 shirts in shades of red, 4 in yellow shades and 5 in green shades . Three shirts are picked at random . the probability that all of those are in red shades is :

Ans.  Probability of picking red shirt is 3/12.  Hence 3/12*3/12*3/12=1/64

Amcat-Q3:   Sangeeta invested rs.20,000 at 8 % per annual . if the interest is compounded half yearly , then total interest earned by Sangeeta at the end of the year is:

Ans.  1632
8% interest yearly can be taken as 4% compounded interest for 2 half years
So Total interest earned=20000[1+(4/100)]^2 - 20000 =21632- 20000= 1632

Amcat-Q4