Math Problem of the week

Attributions: 

The winners from last week were 

Isak

Bartholomew,

Joseph

Boyack,

Camilla

Bush,

Sara

Chandler,

Parker

Coe,

Gage

Fevold,

Ethan

Graham,

Peter

Heap,

David

Heap,

David

Huff,

Callie

Johnson,

Tracee

Jones,

Noah

Lane,

Corinne

Orton,

Molly

Peterson,

Jeffrey

Sass,

Jesse

Shepherd,

Kylie

Smith,

Esther

Zacharias

 

This week's problem is:

A Game of Marbles

Ron and Martin are playing a game with a bowl containing 39 marbles.  Each player takes turns removing 1, 2, 3, or 4 marbles from the bowl.  The person who removes the last marble loses.  If Ron takes the first turn to start the game, how many marbles should he remove to guarantee he is the winner?