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We had very clearly explained solutions to Ten Green Bottles. David from Tithe Barn Primary School, Stockport wrote:

The answer is that the last bottle fell at five minutes to six. I worked this out by writing down the numbers 1-10 and by the first number I put the time when it fell. Then, I added 5 minute intervals and put them at the next number down i.e. 5:10, 5:15, 5:20 etc.

Jeff from Kelly Elementary School in Carlsbad, California agreed with the answer of 5.55.

Airlangga from St Joseph's Catholic Primary School wrote:

5.10 + (5minx9) = 5.55

Alistair from Histon and Impington Infant School used a similar way of working it out to David, but then generalises, leading nicely on from Airlangga's response:

I have spotted that the equation for the nth bottle is 5 x(n-1) minutes after 5.10

Very well thought out all of you.