4*(48) = 4*(40+8) = 4*40 + 4*8 = 160 + 32 = 192
You can think of it as having four copies of 40 added to four copies of 8 which ultimately leads to 160+32 = 192
Alternatively,
4*(48) = 4*(50-2) = 4*50 - 4*2 = 200 - 8 = 192
which may be a shorter route
