Finding the Third Proportional to 717.56 and 1,090.69

Step by Step Solution

1. Step 1: Write the proportion equation
   717.56 : 1,090.69 = 1,090.69 : x
2. Step 2: Convert to fraction form
   717.56/1,090.69 = 1,090.69/x
3. Step 3: Cross multiply
   717.56x = 1,090.69 × 1,090.69
4. Step 4: Simplify right side
   717.56x = 1,189,599.22
5. Step 5: Solve for x
   x = 1,189,599.22/717.56
6. Step 6: Final answer
   x = 1,657.83