Finding the Fourth Proportional to 1,059.46, 1,588.78 and 648.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,059.46 : 1,588.78 = 648.78 : x
2. Step 2: Convert to fraction form
   1,059.46/1,588.78 = 648.78/x
3. Step 3: Cross multiply
   1,059.46x = 1,588.78 × 648.78
4. Step 4: Simplify right side
   1,059.46x = 1,030,768.69
5. Step 5: Solve for x
   x = 1,030,768.69/1,059.46
6. Step 6: Final answer
   x = 972.92