Finding the Fourth Proportional to 1,561.86, 2,155.50 and 898.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,561.86 : 2,155.50 = 898.94 : x
2. Step 2: Convert to fraction form
   1,561.86/2,155.50 = 898.94/x
3. Step 3: Cross multiply
   1,561.86x = 2,155.50 × 898.94
4. Step 4: Simplify right side
   1,561.86x = 1,937,665.17
5. Step 5: Solve for x
   x = 1,937,665.17/1,561.86
6. Step 6: Final answer
   x = 1,240.61