yg no 4 & 8 pliss cepat dijawab buat besok

silahkan lihat gambar ya ka:)
maaf kalau gak jelas...

4)
45 = 20 hari
45 + 5 = X hari

45/50 = x / 20
9/10 = x/20
X = 18

8) 84 = 7
49 = 7 + x
84/49 = 7/7+x
12/7 = 7+ x / 7
12 . 7 = 49 + 7x
84 = 49+ 7x
84 -49 = 7x
35 = 7x
X = 5