Kegiatan kanggo Keluarga

For someone good at adding, multiplying by 3 and 4 can be quick and easy.

Multiplying a number by 3 is adding the number to double the number. So, 3 x 6 is 6 more than double 6, which is 6 + 12 = 18.

Four times a number is doubling a number twice. So, 4 x 7 is 2 x (2 x 7), which is 14 + 14 = 28.