Finding the Fourth Proportional to 1,245.83, 1,719.12 and 686.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,245.83 : 1,719.12 = 686.16 : x
2. Step 2: Convert to fraction form
   1,245.83/1,719.12 = 686.16/x
3. Step 3: Cross multiply
   1,245.83x = 1,719.12 × 686.16
4. Step 4: Simplify right side
   1,245.83x = 1,179,591.38
5. Step 5: Solve for x
   x = 1,179,591.38/1,245.83
6. Step 6: Final answer
   x = 946.84