It looks like you're given

Then by the additivity of definite integrals this is the same as

(presumably this is what the hint suggests to use)
Then by the fundamental theorem of calculus, we have

Are you sure you meant to type "

" ? or did you mean "

"
Y - 12% of y + 3% of y = final cost
may be wrong, havnt done math in a good while
Im not sure but i thing its 0.5 or 1/2
cause if you take (3/1)*(1/6) that's what you will get
also you had to make 3 as a fraction so you would put the denominator as 1 so if you divide 1 and 3 you would still get the whole number as 3
In order to get the total price, we can multiply the 4 dollars by .05 to find 5 percent of the object's cost and add it to the sales tax. So, .05 times 4 is 0.2, meaning there is a sales tax of 0.2 dollars. We add that to the four, so the total price is 4.20 dollars. Hope this helps.