Paul's AMT Base Is $450,000

Essay

Paul's AMT base is $450,000. Green, Inc.'s (a C corporation) AMT base also is $450,000.
a. Calculate the tentative AMT for Paul (assume the higher bracket begins above $175,000).
b. Calculate the tentative AMT for Green, Inc.
c. Why are the amounts in a. and b. not the same since the AMT base for both is $450,000?
d. Would your answer in b. change if Green, Inc. was an S corporation?