Finding the Fourth Proportional to 1,299.10, 1,947.12 and 648.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,299.10 : 1,947.12 = 648.50 : x
2. Step 2: Convert to fraction form
   1,299.10/1,947.12 = 648.50/x
3. Step 3: Cross multiply
   1,299.10x = 1,947.12 × 648.50
4. Step 4: Simplify right side
   1,299.10x = 1,262,707.32
5. Step 5: Solve for x
   x = 1,262,707.32/1,299.10
6. Step 6: Final answer
   x = 971.99