Finding the Fourth Proportional to 1,071.69, 1,615.75 and 1,057.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,071.69 : 1,615.75 = 1,057.87 : x
2. Step 2: Convert to fraction form
   1,071.69/1,615.75 = 1,057.87/x
3. Step 3: Cross multiply
   1,071.69x = 1,615.75 × 1,057.87
4. Step 4: Simplify right side
   1,071.69x = 1,709,253.45
5. Step 5: Solve for x
   x = 1,709,253.45/1,071.69
6. Step 6: Final answer
   x = 1,594.91