Let an integer be chosen at random from the integers 1 to 30 inclusive. find the probability that the integer chosen is divisible by 4 or is greater than 25 and less than 30.

Hence, the required probability is:

                    1/3

Let A denote the event that the integer chosen is divisible by 4.

i.e. A={4,8,12,16,20,24,28}

Hence, P(A)=7/30

and B denote the event that the integer is greater than 25 and is less than 30.

i.e. B={26,27,28,29}

Hence, P(B)=4/30

Hence, A∩B denote the event that the integer us divisible by 4 and is greater than 25 and is less than 30.

i.e. A∩B={28}

Hence, P(A∩B)=1/30

and A∪B denote the event  that the integer chosen is divisible by 4 or is greater than 25 and less than 30.

Hence,we know that:

                  P(A∪B)=P(A)+P(B)-P(A∩B)

i.e.    P(A∪B)=7/30+4/30-1/30

        P(A∪B)=10/30

        P(A∪B)=1/3

x² + 3x + 7 = 0       [ax² + bx + c]

a = 1

b = 3

c = 7

quadratic formula:

    (+/- is this ±)

plug in the numbers into the variables

your answer is a