Finding the Third Proportional to 1,239.19 and 1,870.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,239.19 : 1,870.31 = 1,870.31 : x
2. Step 2: Convert to fraction form
   1,239.19/1,870.31 = 1,870.31/x
3. Step 3: Cross multiply
   1,239.19x = 1,870.31 × 1,870.31
4. Step 4: Simplify right side
   1,239.19x = 3,498,068.85
5. Step 5: Solve for x
   x = 3,498,068.85/1,239.19
6. Step 6: Final answer
   x = 2,822.87