$$5-digit$$ numbers are formed using $$2$$, $$3$$, $$5$$, $$7$$, $$9$$ without repeating the digits. If p is the number of such numbers that exceeds $$20000$$ and q be the number of those that lie between $$30000$$ and $$90000$$ then p : q is:

Question

Infinity Learn · Accepted Answer

Any number $$5-digit$$ formed by $$2$$, $$3$$, $$5$$, $$7$$, $$9$$, exceeds $$20000$$. Therefore, $$p=5$$!$$=120A$$ number will lie between $$30000$$ and $$90000$$ if it begins with $$3$$, $$5$$ or $$7$$ ∴$$q=(3)(4$$!$$)$$.Thus p:$$q=5$$:$$3$$.

5-digit numbers are formed using 2, 3, 5, 7, 9 without repeating the digits. If p is the number of such numbers that exceeds 20000 and q be the number of those that lie between 30000 and 90000 then p : q is:

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