Finding the Fourth Proportional to 1,397.54, 1,928.53 and 776.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,397.54 : 1,928.53 = 776.50 : x
2. Step 2: Convert to fraction form
   1,397.54/1,928.53 = 776.50/x
3. Step 3: Cross multiply
   1,397.54x = 1,928.53 × 776.50
4. Step 4: Simplify right side
   1,397.54x = 1,497,503.55
5. Step 5: Solve for x
   x = 1,497,503.55/1,397.54
6. Step 6: Final answer
   x = 1,071.53