Finding the Fourth Proportional to 33,128.10, 49,692.08 and 13,420.50

Step by Step Solution

1. Step 1: Write the proportion equation
   33,128.10 : 49,692.08 = 13,420.50 : x
2. Step 2: Convert to fraction form
   33,128.10/49,692.08 = 13,420.50/x
3. Step 3: Cross multiply
   33,128.10x = 49,692.08 × 13,420.50
4. Step 4: Simplify right side
   33,128.10x = 666,892,492.54
5. Step 5: Solve for x
   x = 666,892,492.54/33,128.10
6. Step 6: Final answer
   x = 20,130.72