Finding the Fourth Proportional to 1,109.49, 1,531.71 and 667.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.49 : 1,531.71 = 667.50 : x
2. Step 2: Convert to fraction form
   1,109.49/1,531.71 = 667.50/x
3. Step 3: Cross multiply
   1,109.49x = 1,531.71 × 667.50
4. Step 4: Simplify right side
   1,109.49x = 1,022,416.43
5. Step 5: Solve for x
   x = 1,022,416.43/1,109.49
6. Step 6: Final answer
   x = 921.52