I have 13 marbles, Tom has twice as many and Bill has twice the number that Tom has. How many marbles do we have between the three of us?

i have 13 marbles

tom has 13 x 2 = 26 marbles
bill has 26 x 2 = 52 marbles
hence 3 of us have 13+26+52 = 91 marbles

if there are 48 matches in a box how many will there be in 6 boxes

To find out how many marbles you have between the three of you, we need to add up the number of marbles each of you has.

You have 13 marbles.

Tom has twice as many as you, so we can multiply your number of marbles by 2: 13 * 2 = 26 marbles.

Bill has twice the number of marbles that Tom has, so we multiply Tom's number of marbles by 2 as well: 26 * 2 = 52 marbles.

Now we can add up the marbles each of you has: 13 + 26 + 52 = 91 marbles.

Therefore, you have a total of 91 marbles between the three of you.