Finding the Third Proportional to 11,891.81 and 17,871.89

Step by Step Solution

1. Step 1: Write the proportion equation
   11,891.81 : 17,871.89 = 17,871.89 : x
2. Step 2: Convert to fraction form
   11,891.81/17,871.89 = 17,871.89/x
3. Step 3: Cross multiply
   11,891.81x = 17,871.89 × 17,871.89
4. Step 4: Simplify right side
   11,891.81x = 319,404,474.51
5. Step 5: Solve for x
   x = 319,404,474.51/11,891.81
6. Step 6: Final answer
   x = 26,859.19