Finding the Fourth Proportional to 1,648.86, 2,472.12 and 770.43

Step by Step Solution

1. Step 1: Write the proportion equation
   1,648.86 : 2,472.12 = 770.43 : x
2. Step 2: Convert to fraction form
   1,648.86/2,472.12 = 770.43/x
3. Step 3: Cross multiply
   1,648.86x = 2,472.12 × 770.43
4. Step 4: Simplify right side
   1,648.86x = 1,904,595.41
5. Step 5: Solve for x
   x = 1,904,595.41/1,648.86
6. Step 6: Final answer
   x = 1,155.10