Finding the Fourth Proportional to 3,586.86, 5,380.59 and 989.79

Step by Step Solution

1. Step 1: Write the proportion equation
   3,586.86 : 5,380.59 = 989.79 : x
2. Step 2: Convert to fraction form
   3,586.86/5,380.59 = 989.79/x
3. Step 3: Cross multiply
   3,586.86x = 5,380.59 × 989.79
4. Step 4: Simplify right side
   3,586.86x = 5,325,670.10
5. Step 5: Solve for x
   x = 5,325,670.10/3,586.86
6. Step 6: Final answer
   x = 1,484.77