Finding the Fourth Proportional to 42,477.60, 63,700.20 and 12,885.60

Step by Step Solution

1. Step 1: Write the proportion equation
   42,477.60 : 63,700.20 = 12,885.60 : x
2. Step 2: Convert to fraction form
   42,477.60/63,700.20 = 12,885.60/x
3. Step 3: Cross multiply
   42,477.60x = 63,700.20 × 12,885.60
4. Step 4: Simplify right side
   42,477.60x = 820,815,297.12
5. Step 5: Solve for x
   x = 820,815,297.12/42,477.60
6. Step 6: Final answer
   x = 19,323.49