Finding the Third Proportional to 58,578 and 90,780

Step by Step Solution

1. Step 1: Write the proportion equation
   58,578 : 90,780 = 90,780 : x
2. Step 2: Convert to fraction form
   58,578/90,780 = 90,780/x
3. Step 3: Cross multiply
   58,578x = 90,780 × 90,780
4. Step 4: Simplify right side
   58,578x = 8,241,008,400
5. Step 5: Solve for x
   x = 8,241,008,400/58,578
6. Step 6: Final answer
   x = 140,684.36