Finding the Fourth Proportional to 1,437.31, 2,159.57 and 917.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,437.31 : 2,159.57 = 917.55 : x
2. Step 2: Convert to fraction form
   1,437.31/2,159.57 = 917.55/x
3. Step 3: Cross multiply
   1,437.31x = 2,159.57 × 917.55
4. Step 4: Simplify right side
   1,437.31x = 1,981,513.45
5. Step 5: Solve for x
   x = 1,981,513.45/1,437.31
6. Step 6: Final answer
   x = 1,378.63