Finding the Third Proportional to 391 and 1,051.50

Step by Step Solution

1. Step 1: Write the proportion equation
   391 : 1,051.50 = 1,051.50 : x
2. Step 2: Convert to fraction form
   391/1,051.50 = 1,051.50/x
3. Step 3: Cross multiply
   391x = 1,051.50 × 1,051.50
4. Step 4: Simplify right side
   391x = 1,105,652.25
5. Step 5: Solve for x
   x = 1,105,652.25/391
6. Step 6: Final answer
   x = 2,827.76