Finding the Fourth Proportional to 1,433.31, 2,153.57 and 913.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,433.31 : 2,153.57 = 913.55 : x
2. Step 2: Convert to fraction form
   1,433.31/2,153.57 = 913.55/x
3. Step 3: Cross multiply
   1,433.31x = 2,153.57 × 913.55
4. Step 4: Simplify right side
   1,433.31x = 1,967,378.54
5. Step 5: Solve for x
   x = 1,967,378.54/1,433.31
6. Step 6: Final answer
   x = 1,372.61