Finding the Fourth Proportional to 1,117.89, 1,541.70 and 724.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,117.89 : 1,541.70 = 724.50 : x
2. Step 2: Convert to fraction form
   1,117.89/1,541.70 = 724.50/x
3. Step 3: Cross multiply
   1,117.89x = 1,541.70 × 724.50
4. Step 4: Simplify right side
   1,117.89x = 1,116,961.65
5. Step 5: Solve for x
   x = 1,116,961.65/1,117.89
6. Step 6: Final answer
   x = 999.17