Finding the Fourth Proportional to 1,561.20, 2,342.46 and 1,123.70

Step by Step Solution

1. Step 1: Write the proportion equation
   1,561.20 : 2,342.46 = 1,123.70 : x
2. Step 2: Convert to fraction form
   1,561.20/2,342.46 = 1,123.70/x
3. Step 3: Cross multiply
   1,561.20x = 2,342.46 × 1,123.70
4. Step 4: Simplify right side
   1,561.20x = 2,632,222.30
5. Step 5: Solve for x
   x = 2,632,222.30/1,561.20
6. Step 6: Final answer
   x = 1,686.03