Question

Find the least number that can be divided exactly by all odd numbers between $20$ and $30$.

Answer 1

The least number that can be divided exactly by all the odd numbers between 20 and 30
= $LCM(21,23,25,27,29)$
Factors of $21=3\times 7$
Factors of $23=23\times 1$
Factors of $25=5\times 5$
Factors of $27=3\times 3\times 3$
Factors of $29=29\times 1$
Thus,
$LCM(21,23,25,27,29)$ = $3\times 3\times 3\times 5\times 5\times 7\times 23\times 29$
= $3151575$