A customer ordered fifteen Zingers. Zingers are placed in packages of four, three, or one. In how many different ways can this order be filled?

2 Answers
Feb 12, 2017

1515

Explanation:

There are at most 33 packages of four Zingers. Treating each possibility 3, 2, 1, 03,2,1,0 as a separate case, there are then subcases according to the number of packages of three Zingers.

It's probably best to just systematically enumerate them as follows:

o o o ocolor(white)(o)o o o ocolor(white)(o)o o o ocolor(white)(o)o o ooooooooooooooooooo
o o o ocolor(white)(o)o o o ocolor(white)(o)o o o ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ooooooooooooooooooooo

o o o ocolor(white)(o)o o o ocolor(white)(o)o o ocolor(white)(o)o o ocolor(white)(o)oooooooooooooooooooo
o o o ocolor(white)(o)o o o ocolor(white)(o)o o ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)oooooooooooooooooooooo
o o o ocolor(white)(o)o o o ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)oooooooooooooooooooooooo

o o o ocolor(white)(o)o o ocolor(white)(o)o o ocolor(white)(o)o o ocolor(white)(o)ocolor(white)(o)ooooooooooooooooooooo
o o o ocolor(white)(o)o o ocolor(white)(o)o o ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ooooooooooooooooooooooo
o o o ocolor(white)(o)o o ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ooooooooooooooooooooooooo
o o o ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ooooooooooooooooooooooooooo

o o ocolor(white)(o)o o ocolor(white)(o)o o ocolor(white)(o)o o ocolor(white)(o)o o oooooooooooooooooooo
o o ocolor(white)(o)o o ocolor(white)(o)o o ocolor(white)(o)o o ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)oooooooooooooooooooooo
o o ocolor(white)(o)o o ocolor(white)(o)o o ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)oooooooooooooooooooooooo
o o ocolor(white)(o)o o ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)oooooooooooooooooooooooooo
o o ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)oooooooooooooooooooooooooooo
ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)ocolor(white)(o)oooooooooooooooooooooooooooooo

I count 1515 arrangements.

Feb 12, 2017

See below.

Explanation:

Calling {alpha,beta,gamma} in ZZ ge 0 we have

3alpha+2beta+gamma=15

The different solutions to this equation, calling diophantine equation after Diophantus of Alexandria, equals the number of different arrangements.