Finding the Fourth Proportional to 42,881.60, 64,344.32 and 20,417.69

Step by Step Solution

1. Step 1: Write the proportion equation
   42,881.60 : 64,344.32 = 20,417.69 : x
2. Step 2: Convert to fraction form
   42,881.60/64,344.32 = 20,417.69/x
3. Step 3: Cross multiply
   42,881.60x = 64,344.32 × 20,417.69
4. Step 4: Simplify right side
   42,881.60x = 1,313,761,955.21
5. Step 5: Solve for x
   x = 1,313,761,955.21/42,881.60
6. Step 6: Final answer
   x = 30,636.97