Finding the Fourth Proportional to 1,613.81, 2,419.17 and 688.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,613.81 : 2,419.17 = 688.09 : x
2. Step 2: Convert to fraction form
   1,613.81/2,419.17 = 688.09/x
3. Step 3: Cross multiply
   1,613.81x = 2,419.17 × 688.09
4. Step 4: Simplify right side
   1,613.81x = 1,664,606.69
5. Step 5: Solve for x
   x = 1,664,606.69/1,613.81
6. Step 6: Final answer
   x = 1,031.48