Finding the Fourth Proportional to 42,890.08, 64,311.52 and 13,299.72

Step by Step Solution

1. Step 1: Write the proportion equation
   42,890.08 : 64,311.52 = 13,299.72 : x
2. Step 2: Convert to fraction form
   42,890.08/64,311.52 = 13,299.72/x
3. Step 3: Cross multiply
   42,890.08x = 64,311.52 × 13,299.72
4. Step 4: Simplify right side
   42,890.08x = 855,325,208.77
5. Step 5: Solve for x
   x = 855,325,208.77/42,890.08
6. Step 6: Final answer
   x = 19,942.26