There are 10 numbers: 21, 22, 34, 39, 44, 45, 65, 76, 133, and 153. Can you split all the numbers into 2 groups so that the product of all the numbers of these 2 groups are the same? Ans:

The easiest way is to factor all the number out. 21 = 3 x 7, 22 = 2 x 11, 34 = 2 x 17, 39 = 3 x 13, 44 = 2 x 11, 45 = 3 x 3 5, 65 = 5 x 13, 76 = 2 x 2 x 19, 133 = 7 x 19. Then you can try to split the numbers. For example, 133 and 76 should be separated because both of them have factors of 19. These 2 groups are: (76, 21, 65, 22, 153) and (133, 39, 45, 44, 34).