There were two things to discover here; one, is it possible to total exactly 100 with the given set of numbers and two, if it is possible, how many ways can100 be scored.
It took quite a lot of work to solve this seemingly easy problem as Amelia from Belchamp St. Paul Primary School shows in her calculations:
I tried lots of different combinations of numbers and the closest number I got was 101.
| Then I tried this: | 3x17=51 100-51=49 49-17=32 2x16=32 4x17=68 32+68=100 |
So close! Let's see how somebody managed to get a lower total and score the target number.
Tom from Brecknock Primary School used this
strategy:
First I tried 40+39+24=103 then i tried 40+39+23=102
Next I tried all the possible ways to get rid of the extra 2.
I tried 100-16*2=68
I know that 17*4=68, so I added 68+32=100
Below we will see what this means to other problem solvers.
Adam and Anthony from
Moorfield Primary School also persevered until they were
successful:
We tried loads of different possible solutions then we finally
got:
40+17+17+16=100.
The boys used this first solution to find others. They took the greatest of the numbers (40) and then found different combinations of numbers that would total 40.
We used different numbers to make 40
24+16+17+17+16=100
23+17+17+17+16=100
Good work from everybody so far, but were these only possibilities? Anisha from Eastbury Farm School in Hertfordshire, and Lisa, a pupil at W.C.P. School in Manchester and Sarah-Jane of Belchamp St. Paul Primary School think not:
Their Solution: 16+16+17+17+17+17=100
Now have we seen this solution before anywhere?
Are there any more possibilities? Are we sure?