Let \(S=\{x:x \text{ is a positive multiple of }3 \text{ less than }100\}\),

\[ P=\{x:x \text{ is a prime less than }20\} \]

Then, \(n(S)+n(P)\) is

(a) 34

(b) 31

(c) 33

(d) 30

Solution

Positive multiples of \(3\) less than \(100\):

\[ 3,6,9,\ldots,99 \]

Number of elements in \(S\):

\[ \frac{99}{3}=33 \]

Therefore,

\[ n(S)=33 \]

Prime numbers less than \(20\):

\[ 2,3,5,7,11,13,17,19 \]

Thus,

\[ n(P)=8 \]

Hence,

\[ n(S)+n(P)=33+8 \]

\[ =41 \]

Answer

\[ \boxed{41} \]

Hence, none of the given options is correct.

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