Finding the Fourth Proportional to 1,868.10, 2,620.20 and 1,868.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,868.10 : 2,620.20 = 1,868.10 : x
2. Step 2: Convert to fraction form
   1,868.10/2,620.20 = 1,868.10/x
3. Step 3: Cross multiply
   1,868.10x = 2,620.20 × 1,868.10
4. Step 4: Simplify right side
   1,868.10x = 4,894,795.62
5. Step 5: Solve for x
   x = 4,894,795.62/1,868.10
6. Step 6: Final answer
   x = 2,620.20