Finding the Fourth Proportional to 1,142.31, 1,705.20 and 1,003.92

Step by Step Solution

1. Step 1: Write the proportion equation
   1,142.31 : 1,705.20 = 1,003.92 : x
2. Step 2: Convert to fraction form
   1,142.31/1,705.20 = 1,003.92/x
3. Step 3: Cross multiply
   1,142.31x = 1,705.20 × 1,003.92
4. Step 4: Simplify right side
   1,142.31x = 1,711,870.84
5. Step 5: Solve for x
   x = 1,711,870.84/1,142.31
6. Step 6: Final answer
   x = 1,498.60