# Thread: Integral Word Problem

1. ## Integral Word Problem

Hey

I'm stuck on this word problem

Marginal revenue in thousands of dollars is: R'(x) = -0.6x + 7
where x is the number of units sold, in hundreds. Find the revenue if 350 units are sold, assume R(0) = 0

Okay so I did the anti derivative of the equation
with C equalling 0
(-0.6x^2)/2 + 7x/1 = Y

then substituted 350 into the equation

My answer was -34300, my text says the answer is 20825

Where have I gone wrong?????????

thanks in advance.

2. Originally Posted by Mudd_101
Hey

I'm stuck on this word problem

Marginal revenue in thousands of dollars is: R'(x) = -0.6x + 7
where x is the number of units sold, in hundreds. Find the revenue if 350 units are sold, assume R(0) = 0

Okay so I did the anti derivative of the equation
with C equalling 0
(-0.6x^2)/2 + 7x/1 = Y

then substituted 350 into the equation

My answer was -34300, my text says the answer is 20825

Where have I gone wrong?????????

thanks in advance.
Substitute 3.5 (as this needs to be in 100 s
The value of Y will come out in 1000s So multiply the answer you get with 1000

3. thanks