Finding the Fourth Proportional to 1,307.96, 1,804.76 and 776.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,307.96 : 1,804.76 = 776.72 : x
2. Step 2: Convert to fraction form
   1,307.96/1,804.76 = 776.72/x
3. Step 3: Cross multiply
   1,307.96x = 1,804.76 × 776.72
4. Step 4: Simplify right side
   1,307.96x = 1,401,793.19
5. Step 5: Solve for x
   x = 1,401,793.19/1,307.96
6. Step 6: Final answer
   x = 1,071.74