Finding the Fourth Proportional to 1,397.52, 1,928.60 and 776.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,397.52 : 1,928.60 = 776.56 : x
2. Step 2: Convert to fraction form
   1,397.52/1,928.60 = 776.56/x
3. Step 3: Cross multiply
   1,397.52x = 1,928.60 × 776.56
4. Step 4: Simplify right side
   1,397.52x = 1,497,673.62
5. Step 5: Solve for x
   x = 1,497,673.62/1,397.52
6. Step 6: Final answer
   x = 1,071.67