Multiplication can be replace by addition but it is better to use appropriate algorithm. To be able to use algorithm we have to master the results of multiplication of natural numbers in the range of 1 to 9.
We will do it later but now we try to understand the nature of multiplication.
The result of multiplication of two natural numbers let's say A and B can be be expressed by a rectangle having A row and B columns or vice versa. This bring instantly an idea that A x B is the same as B x A.
In our exercise we set the number of columns to be equal to the first to A and the number of rows to be B. This means that if we got for example 7 x 3 we should pain 7 squares in the first row then paint next two rows in the same manner to get the total 3 rows for 7 square each.
The small square can be counted but you may get the result by clicking the last one on the bottom right. The computer will count all correctly pained squars an also the wrong ones.
For every right pained square the p-layer gets 1 point and for the wrong one -1 point. If there are more negative points than the right one the resulting score is 0.
Your cumulative score as well as the score obtained in the last exercises in () are shown in the small window.
The time of exercise is mesured by the timer.
Enjoy!
designed by Witold Wojcik