The answer is: x= 5/12 or x=0.416
To find a percentage of a number, multiply by the decimal form of that percentage(20%=0.20). So, take the cost, $430, and multiply by common state sales tax (7% for me)---430 x 0.07 = 30.10 The sale tax rate is 7%.
Hmm idk if this is what you need, but here we go: Amy is 5 years older than her brother, John. Her age is 19. How old is John?
x-John
x+5=19
x=19-5=14
John is 14.