Finding the Third Proportional to 19,787.50 and 42,170

Step by Step Solution

1. Step 1: Write the proportion equation
   19,787.50 : 42,170 = 42,170 : x
2. Step 2: Convert to fraction form
   19,787.50/42,170 = 42,170/x
3. Step 3: Cross multiply
   19,787.50x = 42,170 × 42,170
4. Step 4: Simplify right side
   19,787.50x = 1,778,308,900
5. Step 5: Solve for x
   x = 1,778,308,900/19,787.50
6. Step 6: Final answer
   x = 89,870.32