Finding the Fourth Proportional to 2,659.86, 3,989.34 and 712.08

Step by Step Solution

1. Step 1: Write the proportion equation
   2,659.86 : 3,989.34 = 712.08 : x
2. Step 2: Convert to fraction form
   2,659.86/3,989.34 = 712.08/x
3. Step 3: Cross multiply
   2,659.86x = 3,989.34 × 712.08
4. Step 4: Simplify right side
   2,659.86x = 2,840,729.23
5. Step 5: Solve for x
   x = 2,840,729.23/2,659.86
6. Step 6: Final answer
   x = 1,068.00