Finding the Fourth Proportional to 1,123.93, 1,686.48 and 1,120.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.93 : 1,686.48 = 1,120.42 : x
2. Step 2: Convert to fraction form
   1,123.93/1,686.48 = 1,120.42/x
3. Step 3: Cross multiply
   1,123.93x = 1,686.48 × 1,120.42
4. Step 4: Simplify right side
   1,123.93x = 1,889,565.92
5. Step 5: Solve for x
   x = 1,889,565.92/1,123.93
6. Step 6: Final answer
   x = 1,681.21