Finding the Fourth Proportional to 1,245.82, 1,719.23 and 686.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,245.82 : 1,719.23 = 686.31 : x
2. Step 2: Convert to fraction form
   1,245.82/1,719.23 = 686.31/x
3. Step 3: Cross multiply
   1,245.82x = 1,719.23 × 686.31
4. Step 4: Simplify right side
   1,245.82x = 1,179,926.46
5. Step 5: Solve for x
   x = 1,179,926.46/1,245.82
6. Step 6: Final answer
   x = 947.11