Finding the Third Proportional to 1,287 and 1,912.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,287 : 1,912.50 = 1,912.50 : x
2. Step 2: Convert to fraction form
   1,287/1,912.50 = 1,912.50/x
3. Step 3: Cross multiply
   1,287x = 1,912.50 × 1,912.50
4. Step 4: Simplify right side
   1,287x = 3,657,656.25
5. Step 5: Solve for x
   x = 3,657,656.25/1,287
6. Step 6: Final answer
   x = 2,842.00