Finding the Fourth Proportional to 1,116.72, 1,678.32 and 922.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,116.72 : 1,678.32 = 922.32 : x
2. Step 2: Convert to fraction form
   1,116.72/1,678.32 = 922.32/x
3. Step 3: Cross multiply
   1,116.72x = 1,678.32 × 922.32
4. Step 4: Simplify right side
   1,116.72x = 1,547,948.10
5. Step 5: Solve for x
   x = 1,547,948.10/1,116.72
6. Step 6: Final answer
   x = 1,386.16