3 per 10 ditambah 50%

3/10 + 50% = 3/10 + 50/100 = 3/10 + 5/10 = 8/10 = 4/5 = 0,8

3/10 + 50% = 3/10 + 50/ 100

= 30/100 + 50/100

= 80/100

80/100= 80%