Finding the Fourth Proportional to 42,451.56, 63,688.86 and 12,870.36

Step by Step Solution

1. Step 1: Write the proportion equation
   42,451.56 : 63,688.86 = 12,870.36 : x
2. Step 2: Convert to fraction form
   42,451.56/63,688.86 = 12,870.36/x
3. Step 3: Cross multiply
   42,451.56x = 63,688.86 × 12,870.36
4. Step 4: Simplify right side
   42,451.56x = 819,698,556.19
5. Step 5: Solve for x
   x = 819,698,556.19/42,451.56
6. Step 6: Final answer
   x = 19,309.03