Finding the Fourth Proportional to 1,123.51, 1,688.30 and 603.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.51 : 1,688.30 = 603.89 : x
2. Step 2: Convert to fraction form
   1,123.51/1,688.30 = 603.89/x
3. Step 3: Cross multiply
   1,123.51x = 1,688.30 × 603.89
4. Step 4: Simplify right side
   1,123.51x = 1,019,547.49
5. Step 5: Solve for x
   x = 1,019,547.49/1,123.51
6. Step 6: Final answer
   x = 907.47