Finding the Fourth Proportional to 1,002.21, 1,382.45 and 648.01

Step by Step Solution

1. Step 1: Write the proportion equation
   1,002.21 : 1,382.45 = 648.01 : x
2. Step 2: Convert to fraction form
   1,002.21/1,382.45 = 648.01/x
3. Step 3: Cross multiply
   1,002.21x = 1,382.45 × 648.01
4. Step 4: Simplify right side
   1,002.21x = 895,839.91
5. Step 5: Solve for x
   x = 895,839.91/1,002.21
6. Step 6: Final answer
   x = 893.87