Finding the Fourth Proportional to 3,456.16, 5,185.14 and 991.17

Step by Step Solution

1. Step 1: Write the proportion equation
   3,456.16 : 5,185.14 = 991.17 : x
2. Step 2: Convert to fraction form
   3,456.16/5,185.14 = 991.17/x
3. Step 3: Cross multiply
   3,456.16x = 5,185.14 × 991.17
4. Step 4: Simplify right side
   3,456.16x = 5,139,351.50
5. Step 5: Solve for x
   x = 5,139,351.50/3,456.16
6. Step 6: Final answer
   x = 1,487.01