Please help with this question

Tomas is making trail mix using granola and walnuts. he can spend a total of $12 on the ingredients. he buys 3 pounds of granola that costs $2.00 per pound. the walnuts cost $6 per pound. he uses the equation to represent the total cost, where x represents the number of pounds of granola and y represents the number of pounds of walnuts. he solves the equation for y, the number of pounds of walnuts he can buy. answer- b tomas added 6 to both sides of the equation instead of subtracting 6. just took the test

33% of college students say they use credit cards because of the rewards program. you randomly select 10 college students and ask each to name the reason he or she uses credit cards. find the probability that the number of college students who say they use credit cards because of the rewards program is (a) exactly two, (b) more than two, and (c) between two and five inclusive. if convenient, use technology to find the probabilities.

What percent of 18 is 24? and plz explain thx.