Finding the Fourth Proportional to 42,894.56, 64,363.78 and 20,430.68

Step by Step Solution

1. Step 1: Write the proportion equation
   42,894.56 : 64,363.78 = 20,430.68 : x
2. Step 2: Convert to fraction form
   42,894.56/64,363.78 = 20,430.68/x
3. Step 3: Cross multiply
   42,894.56x = 64,363.78 × 20,430.68
4. Step 4: Simplify right side
   42,894.56x = 1,314,995,792.77
5. Step 5: Solve for x
   x = 1,314,995,792.77/42,894.56
6. Step 6: Final answer
   x = 30,656.47