Finding the Fourth Proportional to 1,380.10, 2,068.38 and 648.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.10 : 2,068.38 = 648.06 : x
2. Step 2: Convert to fraction form
   1,380.10/2,068.38 = 648.06/x
3. Step 3: Cross multiply
   1,380.10x = 2,068.38 × 648.06
4. Step 4: Simplify right side
   1,380.10x = 1,340,434.34
5. Step 5: Solve for x
   x = 1,340,434.34/1,380.10
6. Step 6: Final answer
   x = 971.26