Finding the Fourth Proportional to 2,638.89, 3,958.53 and 907.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,638.89 : 3,958.53 = 907.50 : x
2. Step 2: Convert to fraction form
   2,638.89/3,958.53 = 907.50/x
3. Step 3: Cross multiply
   2,638.89x = 3,958.53 × 907.50
4. Step 4: Simplify right side
   2,638.89x = 3,592,365.98
5. Step 5: Solve for x
   x = 3,592,365.98/2,638.89
6. Step 6: Final answer
   x = 1,361.32