Finding the Fourth Proportional to 1,071.42, 1,478.04 and 721.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,071.42 : 1,478.04 = 721.50 : x
2. Step 2: Convert to fraction form
   1,071.42/1,478.04 = 721.50/x
3. Step 3: Cross multiply
   1,071.42x = 1,478.04 × 721.50
4. Step 4: Simplify right side
   1,071.42x = 1,066,405.86
5. Step 5: Solve for x
   x = 1,066,405.86/1,071.42
6. Step 6: Final answer
   x = 995.32