Finding the Fourth Proportional to 1,561.31, 2,154.72 and 898.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,561.31 : 2,154.72 = 898.34 : x
2. Step 2: Convert to fraction form
   1,561.31/2,154.72 = 898.34/x
3. Step 3: Cross multiply
   1,561.31x = 2,154.72 × 898.34
4. Step 4: Simplify right side
   1,561.31x = 1,935,671.16
5. Step 5: Solve for x
   x = 1,935,671.16/1,561.31
6. Step 6: Final answer
   x = 1,239.77