Finding the Fourth Proportional to 64,128.60, 88,471.59 and 42,628.74

Step by Step Solution

1. Step 1: Write the proportion equation
   64,128.60 : 88,471.59 = 42,628.74 : x
2. Step 2: Convert to fraction form
   64,128.60/88,471.59 = 42,628.74/x
3. Step 3: Cross multiply
   64,128.60x = 88,471.59 × 42,628.74
4. Step 4: Simplify right side
   64,128.60x = 3,771,432,407.50
5. Step 5: Solve for x
   x = 3,771,432,407.50/64,128.60
6. Step 6: Final answer
   x = 58,810.46