Finding the Fourth Proportional to 42,725.05, 64,088.60 and 13,143.16

Step by Step Solution

1. Step 1: Write the proportion equation
   42,725.05 : 64,088.60 = 13,143.16 : x
2. Step 2: Convert to fraction form
   42,725.05/64,088.60 = 13,143.16/x
3. Step 3: Cross multiply
   42,725.05x = 64,088.60 × 13,143.16
4. Step 4: Simplify right side
   42,725.05x = 842,326,723.98
5. Step 5: Solve for x
   x = 842,326,723.98/42,725.05
6. Step 6: Final answer
   x = 19,715.06