A question from my quiz today

• Sep 8th 2009, 01:00 PM
Chizum
A question from my quiz today
Suppose two boys named Davis, three boys named Jones, and four boys named Smith are arranged at random in a row containing nine seats.
-How many arrangements can be made so that boys wearing the same name will stay together?

I think it's 3 nPr 3.
• Sep 8th 2009, 01:29 PM
Plato
Quote:

Originally Posted by Chizum
Suppose two boys named Davis, three boys named Jones, and four boys named Smith are arranged at random in a row containing nine seats.
-How many arrangements can be made so that boys wearing the same name will stay together?

$\left[ {(2!)(3!)(4!)} \right](3!)$