Finding the Fourth Proportional to 1,191.72, 1,644.90 and 841.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,191.72 : 1,644.90 = 841.80 : x
2. Step 2: Convert to fraction form
   1,191.72/1,644.90 = 841.80/x
3. Step 3: Cross multiply
   1,191.72x = 1,644.90 × 841.80
4. Step 4: Simplify right side
   1,191.72x = 1,384,676.82
5. Step 5: Solve for x
   x = 1,384,676.82/1,191.72
6. Step 6: Final answer
   x = 1,161.91