Finding the Fourth Proportional to 1,392.58, 2,088.72 and 698.68

Step by Step Solution

1. Step 1: Write the proportion equation
   1,392.58 : 2,088.72 = 698.68 : x
2. Step 2: Convert to fraction form
   1,392.58/2,088.72 = 698.68/x
3. Step 3: Cross multiply
   1,392.58x = 2,088.72 × 698.68
4. Step 4: Simplify right side
   1,392.58x = 1,459,346.89
5. Step 5: Solve for x
   x = 1,459,346.89/1,392.58
6. Step 6: Final answer
   x = 1,047.94