If there were 280 students voting, how many more of them named brownies as their favorite dessert than cookies?

Thanks for answering Coolkille98,

Unfortunately you have found how many like brownies NOT how many MORE like brownies than cookies.

70%like brownies,  30% like cookies,  SO  70-40=30% MORE like brownied than Cookies.

30% = 30/100 = 0.30 = 0.3

$${\mathtt{0.3}}{\mathtt{\,\times\,}}{\mathtt{280}} = {\mathtt{84}}$$   students like brownies more than cookies. 

$${\mathtt{280}}{\mathtt{\,\times\,}}{\mathtt{0.7}} = {\mathtt{196}}$$

70% of 280 is 196