Finding the Fourth Proportional to 1,389.18, 2,091.86 and 1,026.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.18 : 2,091.86 = 1,026.50 : x
2. Step 2: Convert to fraction form
   1,389.18/2,091.86 = 1,026.50/x
3. Step 3: Cross multiply
   1,389.18x = 2,091.86 × 1,026.50
4. Step 4: Simplify right side
   1,389.18x = 2,147,294.29
5. Step 5: Solve for x
   x = 2,147,294.29/1,389.18
6. Step 6: Final answer
   x = 1,545.73