Finding the Fourth Proportional to 1,058.42, 1,460.75 and 638.79

Step by Step Solution

1. Step 1: Write the proportion equation
   1,058.42 : 1,460.75 = 638.79 : x
2. Step 2: Convert to fraction form
   1,058.42/1,460.75 = 638.79/x
3. Step 3: Cross multiply
   1,058.42x = 1,460.75 × 638.79
4. Step 4: Simplify right side
   1,058.42x = 933,109.30
5. Step 5: Solve for x
   x = 933,109.30/1,058.42
6. Step 6: Final answer
   x = 881.61