Finding the Fourth Proportional to 1,145.34, 1,715.63 and 870.62

Step by Step Solution

1. Step 1: Write the proportion equation
   1,145.34 : 1,715.63 = 870.62 : x
2. Step 2: Convert to fraction form
   1,145.34/1,715.63 = 870.62/x
3. Step 3: Cross multiply
   1,145.34x = 1,715.63 × 870.62
4. Step 4: Simplify right side
   1,145.34x = 1,493,648.86
5. Step 5: Solve for x
   x = 1,493,648.86/1,145.34
6. Step 6: Final answer
   x = 1,304.11