Finding the Fourth Proportional to 40,128.72, 60,192.80 and 31,371

Step by Step Solution

1. Step 1: Write the proportion equation
   40,128.72 : 60,192.80 = 31,371 : x
2. Step 2: Convert to fraction form
   40,128.72/60,192.80 = 31,371/x
3. Step 3: Cross multiply
   40,128.72x = 60,192.80 × 31,371
4. Step 4: Simplify right side
   40,128.72x = 1,888,308,328.80
5. Step 5: Solve for x
   x = 1,888,308,328.80/40,128.72
6. Step 6: Final answer
   x = 47,056.28