Median of 8,11,8,10,6,7,3x,11,11

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class

Mario has $14.35 left in his wallet. he spent $148.43 for tablecloths. then, he spent $92.05 for napkins. how much money did mario have in his wallet to start with?

Luisa sells stuffed animals. she sells her stuffed elephant for $34.90, and the sales tax is 6% of the sale price. about how much is the sales tax on the elephant?