Finding the Third Proportional to 188,430 and 390,109.50

Step by Step Solution

1. Step 1: Write the proportion equation
   188,430 : 390,109.50 = 390,109.50 : x
2. Step 2: Convert to fraction form
   188,430/390,109.50 = 390,109.50/x
3. Step 3: Cross multiply
   188,430x = 390,109.50 × 390,109.50
4. Step 4: Simplify right side
   188,430x = 152,185,421,990.25
5. Step 5: Solve for x
   x = 152,185,421,990.25/188,430
6. Step 6: Final answer
   x = 807,649.64