Finding the Fourth Proportional to 1,365.57, 2,043.74 and 815.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,365.57 : 2,043.74 = 815.06 : x
2. Step 2: Convert to fraction form
   1,365.57/2,043.74 = 815.06/x
3. Step 3: Cross multiply
   1,365.57x = 2,043.74 × 815.06
4. Step 4: Simplify right side
   1,365.57x = 1,665,779.02
5. Step 5: Solve for x
   x = 1,665,779.02/1,365.57
6. Step 6: Final answer
   x = 1,219.84