Finding the Fourth Proportional to 1,379.86, 2,066.14 and 728.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.86 : 2,066.14 = 728.62 : x
2. Step 2: Convert to fraction form
   1,379.86/2,066.14 = 728.62/x
3. Step 3: Cross multiply
   1,379.86x = 2,066.14 × 728.62
4. Step 4: Simplify right side
   1,379.86x = 1,505,430.93
5. Step 5: Solve for x
   x = 1,505,430.93/1,379.86
6. Step 6: Final answer
   x = 1,091.00