Given in the question,
n(S) = 21, n(T) = 32, n(S ∩ T) = 11, n(S ∪ T) = ?
Using the formula,
n(S ∪ T) = n(S) + n(T) – n(S ∩ T)

Correct Option: C

Given in the question,
n(S) = 21, n(T) = 32, n(S ∩ T) = 11, n(S ∪ T) = ?
Using the formula,
n(S ∪ T) = n(S) + n(T) – n(S ∩ T) = 21 + 32 – 11 = 42
Hence, S ∪ T has 42 elements.

72% + 44% = 116%
∴ 16% → 40
∴ 100% → 40 100 16 × = 250

Correct Option: A

72% + 44% = 116%
∴ 16% → 40
∴ 100% → 40 100 16 × = 250
Hence, 16% workers are there who prefer both drinks which are 40 in number.

NA

Correct Option: C

NA

Required percentage
= 100 – (40 + 25 + 15)
= 100 – 80 = 20%

Correct Option: C

Required percentage
= 100 – (40 + 25 + 15)
= 100 – 80 = 20%

Odd natural numbers are 1,3,5,7,............. so on.......
A natural number is a number that occurs commonly and obviously in nature. As such, it is a whole, non-negative number. The set of natural numbers, denoted N, can be defined in either of two ways: N = {0, 1, 2, 3, ...}

Correct Option: C

A natural number is a number that occurs commonly and obviously in nature. As such, it is a whole, non-negative number. The set of natural numbers, denoted N, can be defined in either of two ways: N = {0, 1, 2, 3, ...}
As per given option.
(a) As no odd natural number is divisible by 2, the set A is empty.
(b) Since no natural number satisfies the equation x + 5 = 0,
∴ B = Φ
(c) Since 2 is an even prime number, i.e., C = {2}, C is not an empty set.
(d) Since there is no natural number between 1 and 2, D is an empty set.