This has another answer that fits better. As base addition is implied with 1+4 = 5, the following sets don’t fit to that, so the idea is to use the numbers there to make an equation that fits. I would say it makes more sense that the common equation would be First number X times second number (Y+1). This fits all shown sets. First equation 1*(4+1) = 5, second: 2*(5+1)=12, third: 3*(6+1)=21 which would make the last one 8*(11+1)=96 This variant would actually make more logical sense with the setup showing that the addition symbol is a trick, but that you don’t need to use the other variables from previous equations, just the concepts.

You could fix the initial equation to fit your premise by just rotating the first set. If the first one read 4+1= 5 instead of 1+4 = 5, then everything would match your current answer and not the one i’ve suggested. As with my suggestion it would become 4*(1+1)= 8.

This has another answer that fits better. As base addition is implied with 1+4 = 5, the following sets don’t fit to that, so the idea is to use the numbers there to make an equation that fits. I would say it makes more sense that the common equation would be First number X times second number (Y+1).

This fits all shown sets. First equation 1*(4+1) = 5, second: 2*(5+1)=12, third: 3*(6+1)=21

which would make the last one 8*(11+1)=96

This variant would actually make more logical sense with the setup showing that the addition symbol is a trick, but that you don’t need to use the other variables from previous equations, just the concepts.

You could fix the initial equation to fit your premise by just rotating the first set.

If the first one read 4+1= 5 instead of 1+4 = 5, then everything would match your current answer and not the one i’ve suggested. As with my suggestion it would become 4*(1+1)= 8.