See: We saw that this would be very hard, so we started this as soon as we could.

Plan: We decided to find the sum of each row by adding 1, 2, 3, 4, 5 and 6 together. This gave us the answer 21. We agreed to make each line equal 21.

Do: When we were doing it, we realized that there were less triangles on the outside than the inside rows, which had more. So we decided to put the smallest numbers, the 1s and some 2s, in the middle. Then we put the 5s and the 6s in the outer triangular points where no 6 or 5 would meet another of the same number. This left two 2s, four 3s and four 4s which we placed symmetrically in the remaining triangles.

Check: We checked by calculating the sum of each row. They all added up to 21 thus proving our solution correct.

Answer: (coloured by us)

Note: A number of teams also found patterns such as 'the total in the purple triangles has to be the same as the total in the blue triangles'.