Finding the Fourth Proportional to 91,209.60, 136,800.72 and 28,872

Step by Step Solution

1. Step 1: Write the proportion equation
   91,209.60 : 136,800.72 = 28,872 : x
2. Step 2: Convert to fraction form
   91,209.60/136,800.72 = 28,872/x
3. Step 3: Cross multiply
   91,209.60x = 136,800.72 × 28,872
4. Step 4: Simplify right side
   91,209.60x = 3,949,710,387.84
5. Step 5: Solve for x
   x = 3,949,710,387.84/91,209.60
6. Step 6: Final answer
   x = 43,303.67