Finding the Fourth Proportional to 1,111.92, 1,665.32 and 763.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.92 : 1,665.32 = 763.76 : x
2. Step 2: Convert to fraction form
   1,111.92/1,665.32 = 763.76/x
3. Step 3: Cross multiply
   1,111.92x = 1,665.32 × 763.76
4. Step 4: Simplify right side
   1,111.92x = 1,271,904.80
5. Step 5: Solve for x
   x = 1,271,904.80/1,111.92
6. Step 6: Final answer
   x = 1,143.88