Finding the Fourth Proportional to 28,099.82, 42,170.48 and 13,308.72

Step by Step Solution

1. Step 1: Write the proportion equation
   28,099.82 : 42,170.48 = 13,308.72 : x
2. Step 2: Convert to fraction form
   28,099.82/42,170.48 = 13,308.72/x
3. Step 3: Cross multiply
   28,099.82x = 42,170.48 × 13,308.72
4. Step 4: Simplify right side
   28,099.82x = 561,235,110.59
5. Step 5: Solve for x
   x = 561,235,110.59/28,099.82
6. Step 6: Final answer
   x = 19,972.91