Finding the Fourth Proportional to 1,479.15, 2,219.31 and 931.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,479.15 : 2,219.31 = 931.23 : x
2. Step 2: Convert to fraction form
   1,479.15/2,219.31 = 931.23/x
3. Step 3: Cross multiply
   1,479.15x = 2,219.31 × 931.23
4. Step 4: Simplify right side
   1,479.15x = 2,066,688.05
5. Step 5: Solve for x
   x = 2,066,688.05/1,479.15
6. Step 6: Final answer
   x = 1,397.21