Finding the Fourth Proportional to 42,915.56, 64,351.38 and 17,948.78

Step by Step Solution

1. Step 1: Write the proportion equation
   42,915.56 : 64,351.38 = 17,948.78 : x
2. Step 2: Convert to fraction form
   42,915.56/64,351.38 = 17,948.78/x
3. Step 3: Cross multiply
   42,915.56x = 64,351.38 × 17,948.78
4. Step 4: Simplify right side
   42,915.56x = 1,155,028,762.32
5. Step 5: Solve for x
   x = 1,155,028,762.32/42,915.56
6. Step 6: Final answer
   x = 26,913.99