Finding the Fourth Proportional to 1,066.38, 1,591.80 and 988.26

Step by Step Solution

1. Step 1: Write the proportion equation
   1,066.38 : 1,591.80 = 988.26 : x
2. Step 2: Convert to fraction form
   1,066.38/1,591.80 = 988.26/x
3. Step 3: Cross multiply
   1,066.38x = 1,591.80 × 988.26
4. Step 4: Simplify right side
   1,066.38x = 1,573,112.27
5. Step 5: Solve for x
   x = 1,573,112.27/1,066.38
6. Step 6: Final answer
   x = 1,475.19