Problem solving: pennies in bags
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Problem solving: pennies in bags
Please could anyone help me on this question.
Sam divided 15 pennies among 4 small bags
He could then pay any sum of money from 1p to 15p, without opening any
bag.
How many pennies did Sam put in each bag?
Sam divided 15 pennies among 4 small bags
He could then pay any sum of money from 1p to 15p, without opening any
bag.
How many pennies did Sam put in each bag?
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Re: Problem solving
8,4,2, and 1
1=1
2=2
3=2+1
4=4
5=4+1
6=4+2
7=4+2+1
8=8
9=8+1
10=8+2
11=8+2+1
12=8+4
13=8+4+1
14=8+4+2
15=8+4+2+1
1=1
2=2
3=2+1
4=4
5=4+1
6=4+2
7=4+2+1
8=8
9=8+1
10=8+2
11=8+2+1
12=8+4
13=8+4+1
14=8+4+2
15=8+4+2+1
Re: Problem solving: pennies in bags
Favourite problem I am sad!
Re: Problem solving: pennies in bags
Another way of looking at this is as expressing numbers in binary (i.e. base 2), where a 1 means include the bag with 2^n pennies, and 0 means don't. For example:
11 (decimal) = 1011 (binary) = 8 + 2 + 1
You can write all the numbers from 0 to 15 with 4 binary digits.
11 (decimal) = 1011 (binary) = 8 + 2 + 1
You can write all the numbers from 0 to 15 with 4 binary digits.