Finding the Fourth Proportional to 5,561.96, 7,664.90 and 3,987.32

Step by Step Solution

1. Step 1: Write the proportion equation
   5,561.96 : 7,664.90 = 3,987.32 : x
2. Step 2: Convert to fraction form
   5,561.96/7,664.90 = 3,987.32/x
3. Step 3: Cross multiply
   5,561.96x = 7,664.90 × 3,987.32
4. Step 4: Simplify right side
   5,561.96x = 30,562,409.07
5. Step 5: Solve for x
   x = 30,562,409.07/5,561.96
6. Step 6: Final answer
   x = 5,494.90