Finding the Fourth Proportional to 1,282.89, 1,770.35 and 715.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,282.89 : 1,770.35 = 715.69 : x
2. Step 2: Convert to fraction form
   1,282.89/1,770.35 = 715.69/x
3. Step 3: Cross multiply
   1,282.89x = 1,770.35 × 715.69
4. Step 4: Simplify right side
   1,282.89x = 1,267,021.79
5. Step 5: Solve for x
   x = 1,267,021.79/1,282.89
6. Step 6: Final answer
   x = 987.63