Finding the Fourth Proportional to 42,789.64, 64,180.40 and 13,199.52

Step by Step Solution

1. Step 1: Write the proportion equation
   42,789.64 : 64,180.40 = 13,199.52 : x
2. Step 2: Convert to fraction form
   42,789.64/64,180.40 = 13,199.52/x
3. Step 3: Cross multiply
   42,789.64x = 64,180.40 × 13,199.52
4. Step 4: Simplify right side
   42,789.64x = 847,150,473.41
5. Step 5: Solve for x
   x = 847,150,473.41/42,789.64
6. Step 6: Final answer
   x = 19,798.03