2、3 1.8x 1.2 = 1.2x 3 1.8(2.5+3.5)x4 = 2.5x 4+3.5x 4( 1.5x 1.2)X6 = 1.2x( 1.5x 6)
3、3. 15 3.24 2.86
4、2033.9/ 12~ 169.5
5. 1x4=4 (box) 52-4=48 (person) 48/4= 12 (box) One box contains 12 boxes.
Some topics are actually very simple, as long as you work hard.