Finding the Fourth Proportional to 1,123.07, 1,687.01 and 1,086.17

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.07 : 1,687.01 = 1,086.17 : x
2. Step 2: Convert to fraction form
   1,123.07/1,687.01 = 1,086.17/x
3. Step 3: Cross multiply
   1,123.07x = 1,687.01 × 1,086.17
4. Step 4: Simplify right side
   1,123.07x = 1,832,365.79
5. Step 5: Solve for x
   x = 1,832,365.79/1,123.07
6. Step 6: Final answer
   x = 1,631.58