Finding the Fourth Proportional to 8,970.89, 12,379.47 and 4,991.91

Step by Step Solution

1. Step 1: Write the proportion equation
   8,970.89 : 12,379.47 = 4,991.91 : x
2. Step 2: Convert to fraction form
   8,970.89/12,379.47 = 4,991.91/x
3. Step 3: Cross multiply
   8,970.89x = 12,379.47 × 4,991.91
4. Step 4: Simplify right side
   8,970.89x = 61,797,200.09
5. Step 5: Solve for x
   x = 61,797,200.09/8,970.89
6. Step 6: Final answer
   x = 6,888.64