JA(7) saw that 120 is a multiple of 20 and worked out that '20 x 6' was 120.

L said '2 x 60'.

Adult visitor P said that seven year olds probably wouldn't know anything higher than their twelve times tables and said '12 x 10'.

You lot had...

10 x 12 - two people

6 x 20 - three people

3 x 40 - one person

2 x 60 - two people

1 x 120 - one person

Three people gave lots of answers, typically all the natural (1, 2, 3, ..) ones

One person said that 'number' doesn't mean 'integer', which is true, but you weren't asked to give every possible answer, just (at least) one possible one. The marking notes said that (for example) 240 x 1/2 was to be treated as correct, for example.

One person said 30 x 40, which alas is 1,200. Of course, those could have been the numbers Harry picked too - it doesn't say he got the sum right :)

I'm afraid I suspect Paul's attempt (two complex numbers) would get no marks, although this is partly my prejudice about the maths of infant school teachers: would they recognise the answer as being correct?