Finding the Fourth Proportional to 1,121.41, 1,547.40 and 648.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,121.41 : 1,547.40 = 648.91 : x
2. Step 2: Convert to fraction form
   1,121.41/1,547.40 = 648.91/x
3. Step 3: Cross multiply
   1,121.41x = 1,547.40 × 648.91
4. Step 4: Simplify right side
   1,121.41x = 1,004,123.33
5. Step 5: Solve for x
   x = 1,004,123.33/1,121.41
6. Step 6: Final answer
   x = 895.41