Finding the Fourth Proportional to 1,160.70, 1,601.82 and 636.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,160.70 : 1,601.82 = 636.78 : x
2. Step 2: Convert to fraction form
   1,160.70/1,601.82 = 636.78/x
3. Step 3: Cross multiply
   1,160.70x = 1,601.82 × 636.78
4. Step 4: Simplify right side
   1,160.70x = 1,020,006.94
5. Step 5: Solve for x
   x = 1,020,006.94/1,160.70
6. Step 6: Final answer
   x = 878.79