Finding the Fourth Proportional to 9,914.40, 14,871.78 and 3,991.86

Step by Step Solution

1. Step 1: Write the proportion equation
   9,914.40 : 14,871.78 = 3,991.86 : x
2. Step 2: Convert to fraction form
   9,914.40/14,871.78 = 3,991.86/x
3. Step 3: Cross multiply
   9,914.40x = 14,871.78 × 3,991.86
4. Step 4: Simplify right side
   9,914.40x = 59,366,063.71
5. Step 5: Solve for x
   x = 59,366,063.71/9,914.40
6. Step 6: Final answer
   x = 5,987.86