Finding the Third Proportional to 58,390 and 90,310

Step by Step Solution

1. Step 1: Write the proportion equation
   58,390 : 90,310 = 90,310 : x
2. Step 2: Convert to fraction form
   58,390/90,310 = 90,310/x
3. Step 3: Cross multiply
   58,390x = 90,310 × 90,310
4. Step 4: Simplify right side
   58,390x = 8,155,896,100
5. Step 5: Solve for x
   x = 8,155,896,100/58,390
6. Step 6: Final answer
   x = 139,679.67