Finding the Fourth Proportional to 931.02, 1,293.71 and 920.89

Step by Step Solution

1. Step 1: Write the proportion equation
   931.02 : 1,293.71 = 920.89 : x
2. Step 2: Convert to fraction form
   931.02/1,293.71 = 920.89/x
3. Step 3: Cross multiply
   931.02x = 1,293.71 × 920.89
4. Step 4: Simplify right side
   931.02x = 1,191,364.60
5. Step 5: Solve for x
   x = 1,191,364.60/931.02
6. Step 6: Final answer
   x = 1,279.63