Am I calculating the Marginal Revenue when you get the quantity for the price of $6,000.00? I get zero?

Question

Is this right?

Quantity=Q
Price=P
Total Revenue-TR
Fixed Cost=FC
Margin Cost-MC
Marginal Renenue=MR

___P_____Q______TR________MC____MR
$8,000|5,000|40,000,000|$1,000|$8,000
$7,000|6,000|42,000,000|$1,000|$2,000
$6,000|7,000|42,000,000|$1,000|0
$5,000|8,000|40,000,000|$1,000|$2,000

Answer 1

I believe you are mostly right. I don't see where the first MR value of $8000 comes from. (the first MR value should be undeterminable.) The change (MR) in TR from going from 5000Q to 6000Q is 2000, (correct in your table). The MR going from 6000Q to 7000Q is 0 (also correct in your table). The MR going from 7000 to 8000 is -2000 (wrong sign in your MR column).