Question

Among the positive integers less than or equal to 100, let A be the set of even integers and let B be the  set of integers divisible by 5, How many integers are even or divisible by 5?
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PLZZ answer it's urgent...
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Answer 1

Answer:

60

Step-by-step explanation:

A={2,4,6,....100}

i.e, there are 50 even numbers

B={5,10,15,20,25,....,100}

i.e, there are 20 numbers

50+20-10=60

here 10 numbers which are both even and divisible by 5 are subtracted as it is included in both sets

i.e, 10,20,30,40,50,60,70,80,90,100

Answer 2

Answer:

$\huge\bold\red{SOLUTION}$

◇ A = set of even positive integers less than or equals to 100

A = {2, 4, 6, ......., 100}

⟹ n(A) = 50

◇ B = Set of positive integers divisible by 5 less than or equals to 100

B = {5, 10, 15, ........, 100}

⟹ n(B) = 20

◇ Now, A ∩ B = {10, 20, 30, ....., 100}

⟹ n(A ∩ B) = 10

◇ Now, n(A U B) = n(A) + n(B) - n(A ∩ B)

⟹ n(A U B) = 50 + 20 - 10 = 60

$\huge \fcolorbox{black}{cyan}{◇Hope it helps U◇}$