Finding the Fourth Proportional to 1,173.80, 1,618.72 and 854.47

Step by Step Solution

1. Step 1: Write the proportion equation
   1,173.80 : 1,618.72 = 854.47 : x
2. Step 2: Convert to fraction form
   1,173.80/1,618.72 = 854.47/x
3. Step 3: Cross multiply
   1,173.80x = 1,618.72 × 854.47
4. Step 4: Simplify right side
   1,173.80x = 1,383,145.48
5. Step 5: Solve for x
   x = 1,383,145.48/1,173.80
6. Step 6: Final answer
   x = 1,178.34