Finding the Fourth Proportional to 1,085.16, 1,629.18 and 647.22

Step by Step Solution

1. Step 1: Write the proportion equation
   1,085.16 : 1,629.18 = 647.22 : x
2. Step 2: Convert to fraction form
   1,085.16/1,629.18 = 647.22/x
3. Step 3: Cross multiply
   1,085.16x = 1,629.18 × 647.22
4. Step 4: Simplify right side
   1,085.16x = 1,054,437.88
5. Step 5: Solve for x
   x = 1,054,437.88/1,085.16
6. Step 6: Final answer
   x = 971.69