bantu ya kakak soalnya mau di kumpulin besok nih plis

no 1.
[tex] 25 \times 25 =375 \\ [/tex]
no 4.
[tex](250 + 200) \div 25 \times 50 = \\ = 450 \div 25 \times 50 \\ = 18 \times 50 \\ = 900[/tex]

1.25 x 25= 625x 25=15625
2.28:2=14x14x22/7=616:308
   15x28=420+308=728
3.14x15x20:2=2100
4.250+200=450:25=18x50=900
5. 2 3/4 x 1/2 : 2/4=11/4 x 1/2 x 4/2= 11/4=2 3/4