In SUM mode you have to complete the pyramid. Sometimes you are not asked for the sum of two known addends, but for one of the addends, knowing the sum and the other addend.

In the example in the picture, the number to enter is 13 because 0 + 13 = 13.

In PRODUCT mode you have to complete the pyramid. Sometimes you are not asked for the product of two known factors, but for one of the factors, knowing the product and the other factor.

In the example in the picture, the number to enter is 3 because 3 × 1 = 3.

In SQUARES mode you have to find the product of two equal numbers. Only numbers ending in 0 or 5 appear. If the number ends in 0 the calculation is very simple: for example, 60 × 60 = 3600, so you just square 6 and add the two zeros at the end.

If the number ends in 5, there is a strategy that makes the calculation easier. An example: for 35 × 35, work out 3 × 4 = 12 and then write 25 after it. Indeed, 35 × 35 is 1225.
In general, multiply the tens digit by the next number and then always write 25 after it. As another example, 75 × 75 is 5625 (because 7 × 8 = 56).

Before playing SQUARES PLUS mode it is best to feel confident in SQUARES mode. In this mode you get products of two numbers whose mean always ends in 0 or 5. For example, 43 × 47 can appear, because the mean of 43 and 47 is 45. To answer correctly, use the identity sum times difference, (x+y)(x−y) = x² – y². To work out 43 × 47, take the mean of 43 and 47 and rewrite the product as (45–2) × (45+2); by the identity, (45–2) × (45+2) = 45² – 2² = 2025 – 4 (the last step is exactly the square of a number ending in 5). Another example: for 69 × 71 you do (70–1) × (70+1) = 70² – 1² = 4900 – 1 = 4899.

In SUM PLUS mode the pyramids have three levels. In a three-level pyramid, each brick holds the sum of the two numbers below it.

The first of the two pictures below shows the pyramid to complete; the second shows the solution.

In PRODUCT PLUS mode you multiply a one-digit number by a two-digit number. The calculation is often not easy and, especially at the beginning, pen and paper help.

Some small tricks make it easier in certain cases. Instead of multiplying by 9 you can multiply by 10 – 1: for example, 28 × 9 = 28 × (10 – 1) = 280 – 28 = 252. Instead of multiplying by 5 you can multiply by 10 ÷ 2: for example, 42 × 5 = 42 × 10 ÷ 2 = 420 ÷ 2 = 210.

Before playing PRODUCT EXTRA mode it is best to feel confident in PRODUCT PLUS mode and with the whole game. In this mode you get products of numbers with the same tens digit. An example: for 61 × 64, add the units of one factor to the other factor (either way you get 65). Then multiply 65 by the tens digit (here 6), which gives 65 × 6 = 390, and write the product of the units after it. Indeed, 61 × 64 = 3904. Another example: for 33 × 32 you first get 35, to multiply by 3. From 35 × 3 = 105 you get the result 33 × 32 = 1056.