Tolong jawab no 3 dan 4

3) 12,8 ÷ 1/25 +6 1/4 - 132,9
= 128/10 ÷ 1/25 + 25/4 - 1329/10
= 64/5 × 25 + 25/4 - 1329/10
= 64 × 5 + 25/4 - 1329/10
= 320 + 25/4 - 1329/10
= 3867/20


4) 11 3/4 + 6 3/8 - 0,8 × 3,6
= 47/4 + 51/8 -2,88
= 47/4 + 51/8 - 72/25
= 3049/200