Finding the Fourth Proportional to 1,117.78, 1,541.59 and 719.51

Step by Step Solution

1. Step 1: Write the proportion equation
   1,117.78 : 1,541.59 = 719.51 : x
2. Step 2: Convert to fraction form
   1,117.78/1,541.59 = 719.51/x
3. Step 3: Cross multiply
   1,117.78x = 1,541.59 × 719.51
4. Step 4: Simplify right side
   1,117.78x = 1,109,189.42
5. Step 5: Solve for x
   x = 1,109,189.42/1,117.78
6. Step 6: Final answer
   x = 992.31