Finding the Fourth Proportional to 1,678.89, 2,316.90 and 932.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,678.89 : 2,316.90 = 932.88 : x
2. Step 2: Convert to fraction form
   1,678.89/2,316.90 = 932.88/x
3. Step 3: Cross multiply
   1,678.89x = 2,316.90 × 932.88
4. Step 4: Simplify right side
   1,678.89x = 2,161,401.86
5. Step 5: Solve for x
   x = 2,161,401.86/1,678.89
6. Step 6: Final answer
   x = 1,287.40