The number of 3 -digit numbers, that are divisible by 2 and 3 , but not divisible by 4 and 9 , is _________.
Answer (integer)
125
Solution
<p>No, of 3 digits $=999-99=900$</p>
<p>No. of 3 digit numbers divisible by 2 & 3 i.e. by 6</p>
<p>$\frac{900}{6}=150$</p>
<p>No. of 3 digit numbers divisible by 4 & 9 i.e. by 36</p>
<p>$\frac{900}{36}=25$</p>
<p>$\therefore$ No of 3 digit numbers divisible by $2 \& 3$ but not by $4 \& 9$</p>
<p>$150-25=125$</p>
About this question
Subject: Mathematics · Chapter: Permutations and Combinations · Topic: Fundamental Counting Principle
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