Posted by rich on Sunday, August 19, 2012 at 1:07am.
Now that he has the extra 5 marbles, his number must be a multiple of 13, that is, it divides evenly by 13
So obviously before he had the 5 his number must have had a remainder of 5 when divided by 13
e.g suppose he originally had 320
when divided by 13 we get 24 rown with 5 marbles left over. So he gets 5 from his friend and now has 325 , which divides by 13 to get 25 rows.
let me try this again.
Now that he has the extra 5 marbles, his number must be a multiple of 13, that is, it divides evenly by 13
So obviously before he had the 5 his number must have had a remainder of 13-5 or 8 when divided by 13
e.g suppose he originally had 320
when divided by 13 we get 24 rown with 8 marbles left over. So he gets 5 from his friend and now has 325 , which divides by 13 to get 25 rows.
325÷13=25 R 0
324÷13 =24 R 12
323÷13=24 R 11
322÷13 = 24 R 10
321÷13 = 24 R 9
320÷13 = 24 R 8
320÷13 = 24 R 7
etc
Related Questions
MATH - Allen started out with x marbles. He doubled his number of marbles by ...
Math - Liz, jas and Sam each have a collection of marbles. The three of them ...
math - a bag of marbles can be divided evenly among two, three, or four friends...
math - Jack and Jill got an equal number of marbles from their grandpa's ...
Math - a bag contains 3 red marbles, 5 blue marbles, 2 yellow marbles, and 2 ...
math - Jose was playing a game with marbles.In the first round ,he lost 1/4 of ...
math - in a jar of 40 marbles there are 12 red marbles 19 blue marbles and there...
math - George has a bag of marbles. Inside the bag are 5 red marbles, 3 green ...
math - George has a bag of marbles. Inside the bag are 5 red marbles, 3 green ...
8th grade math - George has a bag of marbles. Inside the bag are 5 red marbles, ...
For Further Reading