Finding the Fourth Proportional to 1,209.89, 1,815.51 and 1,117.01

Step by Step Solution

1. Step 1: Write the proportion equation
   1,209.89 : 1,815.51 = 1,117.01 : x
2. Step 2: Convert to fraction form
   1,209.89/1,815.51 = 1,117.01/x
3. Step 3: Cross multiply
   1,209.89x = 1,815.51 × 1,117.01
4. Step 4: Simplify right side
   1,209.89x = 2,027,942.83
5. Step 5: Solve for x
   x = 2,027,942.83/1,209.89
6. Step 6: Final answer
   x = 1,676.14