Finding the Third Proportional to 42,390 and 90,432

Step by Step Solution

1. Step 1: Write the proportion equation
   42,390 : 90,432 = 90,432 : x
2. Step 2: Convert to fraction form
   42,390/90,432 = 90,432/x
3. Step 3: Cross multiply
   42,390x = 90,432 × 90,432
4. Step 4: Simplify right side
   42,390x = 8,177,946,624
5. Step 5: Solve for x
   x = 8,177,946,624/42,390
6. Step 6: Final answer
   x = 192,921.60