Finding the Fourth Proportional to 9,899.74, 13,661.70 and 5,423.53

Step by Step Solution

1. Step 1: Write the proportion equation
   9,899.74 : 13,661.70 = 5,423.53 : x
2. Step 2: Convert to fraction form
   9,899.74/13,661.70 = 5,423.53/x
3. Step 3: Cross multiply
   9,899.74x = 13,661.70 × 5,423.53
4. Step 4: Simplify right side
   9,899.74x = 74,094,544.37
5. Step 5: Solve for x
   x = 74,094,544.37/9,899.74
6. Step 6: Final answer
   x = 7,484.50