Finding the Fourth Proportional to 1,123.73, 1,685.78 and 507.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.73 : 1,685.78 = 507.42 : x
2. Step 2: Convert to fraction form
   1,123.73/1,685.78 = 507.42/x
3. Step 3: Cross multiply
   1,123.73x = 1,685.78 × 507.42
4. Step 4: Simplify right side
   1,123.73x = 855,398.49
5. Step 5: Solve for x
   x = 855,398.49/1,123.73
6. Step 6: Final answer
   x = 761.21