Finding the Fourth Proportional to 2,100.57, 2,898.48 and 1,216.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,100.57 : 2,898.48 = 1,216.20 : x
2. Step 2: Convert to fraction form
   2,100.57/2,898.48 = 1,216.20/x
3. Step 3: Cross multiply
   2,100.57x = 2,898.48 × 1,216.20
4. Step 4: Simplify right side
   2,100.57x = 3,525,131.38
5. Step 5: Solve for x
   x = 3,525,131.38/2,100.57
6. Step 6: Final answer
   x = 1,678.18