Finding the Fourth Proportional to 1,109.86, 1,531.66 and 667.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.86 : 1,531.66 = 667.96 : x
2. Step 2: Convert to fraction form
   1,109.86/1,531.66 = 667.96/x
3. Step 3: Cross multiply
   1,109.86x = 1,531.66 × 667.96
4. Step 4: Simplify right side
   1,109.86x = 1,023,087.61
5. Step 5: Solve for x
   x = 1,023,087.61/1,109.86
6. Step 6: Final answer
   x = 921.82