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Let $$S$$ be the sample space of all five digit numbers. If $$p$$ is the probability that a randomly selected number from $$S$$, is a multiple of $$7$$ but not divisible by $$5$$, then $$9p$$ is equal to
Let
$$S=\{\text{all five digit numbers}\}$$
Total number of five digit numbers is
$$99999-10000+1=90000$$
Hence,
$$n(S)=90000$$
Now count five digit numbers divisible by $$7.$$
Smallest five digit multiple of $$7$$ is
$$10003$$
Largest five digit multiple of $$7$$ is
$$99995$$
Using
$$n=\frac{l-a}{d}+1,$$
number of multiples of $$7$$ is
$$n=\frac{99995-10003}{7}+1$$
$$=\frac{89992}{7}+1$$
$$=12856+1$$
$$=12857$$
Now count numbers divisible by both $$7$$ and $$5,$$ i.e., divisible by $$35.$$
Smallest five digit multiple of $$35$$ is
$$10010$$
Largest five digit multiple of $$35$$ is
$$99995$$
Hence,
$$n=\frac{99995-10010}{35}+1$$
$$=\frac{89985}{35}+1$$
$$=2571+1$$
$$=2572$$
Therefore, favorable numbers are
$$12857-2572=10285$$
Thus,
$$p=\frac{10285}{90000}$$
$$=\frac{2057}{18000}$$
Hence,
$$9p=\frac{2057}{2000}$$
Therefore,the required value is
$$\boxed{1.0285}$$.
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