Finding the Fourth Proportional to 1,071.32, 1,478.58 and 678.38

Step by Step Solution

1. Step 1: Write the proportion equation
   1,071.32 : 1,478.58 = 678.38 : x
2. Step 2: Convert to fraction form
   1,071.32/1,478.58 = 678.38/x
3. Step 3: Cross multiply
   1,071.32x = 1,478.58 × 678.38
4. Step 4: Simplify right side
   1,071.32x = 1,003,039.10
5. Step 5: Solve for x
   x = 1,003,039.10/1,071.32
6. Step 6: Final answer
   x = 936.26