This is how we completed the nrich pyramid problem step by step.
First we read the instructions until we understood the problem.
Next we counted the number of squares in each layer starting from the North West corner going right and added them together as we went along; the answers were: 1+4=5+9=14+16=30+25=55+36=91.
We then looked at the first question which was: what number cubes are vertically underneath (in a straight line):
The cube that is the number 1?
The cube that is the number 4?
The cube that is the number 8?
Then we attempted to solve the first question.
Soon we realized that the numbers went in a straight line through the middle of the pyramid.
We found out that only layers that worked were odd.
Those were: layer 3&5 and the numbers: 10&43
After we solved that question we moved on to the next which was the same question just a different starting number.
The next question was harder but we solved it as well.
The answer was: 53 and 13.
The next few answers were similar.
At that point we were on a roll.
For the last 4 questions we worked out they were the same as the first three but the last one was simple.
The answer was no.