When calculating a person's rank from the bottom, remember the formula: \[ \text{Rank from bottom} = \text{Total students} -\text{Rank from top} + 1. \] This is a quick way to switch between ranks from top and bottom.
Step 1: Understand the Problem
Alisha's position from the top is 15th.
Manav is 4 positions higher than Alisha, placing Manav at: \[ \text{Manav's rank from top} = 15 -4 = 11. \]
Step 2: Calculate Manav’s Rank from the Bottom
For a class of 20 students, the rank from the bottom is determined by: \[ \text{Rank from bottom} = \text{Total students} -\text{Rank from top} + 1. \]
Using the given values: \[ \text{Rank from bottom} = 20 -11 + 1 = 10. \]
Step 3: Conclude the Result
Manav's rank from the bottom is 10th. Final Answer: Manav's rank from the bottom is (a) 10th.