Finding the Fourth Proportional to 1,156.80, 1,597.72 and 765.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,156.80 : 1,597.72 = 765.60 : x
2. Step 2: Convert to fraction form
   1,156.80/1,597.72 = 765.60/x
3. Step 3: Cross multiply
   1,156.80x = 1,597.72 × 765.60
4. Step 4: Simplify right side
   1,156.80x = 1,223,214.43
5. Step 5: Solve for x
   x = 1,223,214.43/1,156.80
6. Step 6: Final answer
   x = 1,057.41