Finding the Fourth Proportional to 1,091.80, 1,635.27 and 658.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,091.80 : 1,635.27 = 658.05 : x
2. Step 2: Convert to fraction form
   1,091.80/1,635.27 = 658.05/x
3. Step 3: Cross multiply
   1,091.80x = 1,635.27 × 658.05
4. Step 4: Simplify right side
   1,091.80x = 1,076,089.42
5. Step 5: Solve for x
   x = 1,076,089.42/1,091.80
6. Step 6: Final answer
   x = 985.61