Finding the Third Proportional to 143,784 and 312,407.50

Step by Step Solution

1. Step 1: Write the proportion equation
   143,784 : 312,407.50 = 312,407.50 : x
2. Step 2: Convert to fraction form
   143,784/312,407.50 = 312,407.50/x
3. Step 3: Cross multiply
   143,784x = 312,407.50 × 312,407.50
4. Step 4: Simplify right side
   143,784x = 97,598,446,056.25
5. Step 5: Solve for x
   x = 97,598,446,056.25/143,784
6. Step 6: Final answer
   x = 678,785.16