Finding the Fourth Proportional to 1,061.20, 1,463.91 and 687.70

Step by Step Solution

1. Step 1: Write the proportion equation
   1,061.20 : 1,463.91 = 687.70 : x
2. Step 2: Convert to fraction form
   1,061.20/1,463.91 = 687.70/x
3. Step 3: Cross multiply
   1,061.20x = 1,463.91 × 687.70
4. Step 4: Simplify right side
   1,061.20x = 1,006,730.91
5. Step 5: Solve for x
   x = 1,006,730.91/1,061.20
6. Step 6: Final answer
   x = 948.67