Finding the Fourth Proportional to 42,813.40, 64,196.76 and 13,225.72

Step by Step Solution

1. Step 1: Write the proportion equation
   42,813.40 : 64,196.76 = 13,225.72 : x
2. Step 2: Convert to fraction form
   42,813.40/64,196.76 = 13,225.72/x
3. Step 3: Cross multiply
   42,813.40x = 64,196.76 × 13,225.72
4. Step 4: Simplify right side
   42,813.40x = 849,048,372.67
5. Step 5: Solve for x
   x = 849,048,372.67/42,813.40
6. Step 6: Final answer
   x = 19,831.37