Finding the Fourth Proportional to 1,561.98, 2,155.62 and 898.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,561.98 : 2,155.62 = 898.86 : x
2. Step 2: Convert to fraction form
   1,561.98/2,155.62 = 898.86/x
3. Step 3: Cross multiply
   1,561.98x = 2,155.62 × 898.86
4. Step 4: Simplify right side
   1,561.98x = 1,937,600.59
5. Step 5: Solve for x
   x = 1,937,600.59/1,561.98
6. Step 6: Final answer
   x = 1,240.48