Finding the Third Proportional to 799.59 and 1,239.89

Step by Step Solution

1. Step 1: Write the proportion equation
   799.59 : 1,239.89 = 1,239.89 : x
2. Step 2: Convert to fraction form
   799.59/1,239.89 = 1,239.89/x
3. Step 3: Cross multiply
   799.59x = 1,239.89 × 1,239.89
4. Step 4: Simplify right side
   799.59x = 1,537,328.76
5. Step 5: Solve for x
   x = 1,537,328.76/799.59
6. Step 6: Final answer
   x = 1,922.64