Finding the Fourth Proportional to 1,111.06, 1,666.56 and 533.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.06 : 1,666.56 = 533.80 : x
2. Step 2: Convert to fraction form
   1,111.06/1,666.56 = 533.80/x
3. Step 3: Cross multiply
   1,111.06x = 1,666.56 × 533.80
4. Step 4: Simplify right side
   1,111.06x = 889,609.73
5. Step 5: Solve for x
   x = 889,609.73/1,111.06
6. Step 6: Final answer
   x = 800.69