Finding the Fourth Proportional to 1,300.72, 1,794.72 and 776.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,300.72 : 1,794.72 = 776.80 : x
2. Step 2: Convert to fraction form
   1,300.72/1,794.72 = 776.80/x
3. Step 3: Cross multiply
   1,300.72x = 1,794.72 × 776.80
4. Step 4: Simplify right side
   1,300.72x = 1,394,138.50
5. Step 5: Solve for x
   x = 1,394,138.50/1,300.72
6. Step 6: Final answer
   x = 1,071.82