Finding the Third Proportional to 1,042.50 and 1,390.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,042.50 : 1,390.75 = 1,390.75 : x
2. Step 2: Convert to fraction form
   1,042.50/1,390.75 = 1,390.75/x
3. Step 3: Cross multiply
   1,042.50x = 1,390.75 × 1,390.75
4. Step 4: Simplify right side
   1,042.50x = 1,934,185.56
5. Step 5: Solve for x
   x = 1,934,185.56/1,042.50
6. Step 6: Final answer
   x = 1,855.33