What would be the value of investment multiplier if MPC = MPS ?

The correct answer is : 2 times.

Given MPS=MPC

We know that MPC + MPS =1

=> 2 MPS= 1

=> MPS= 1/2

=> MPS= 0.5

The investment multiplier formula is:

Multiplier = 1 / 1- MPC

                = 1 / MPS

                =1/0.5

                = 2 Times