Finding the Fourth Proportional to 1,429.70, 1,973.02 and 870.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,429.70 : 1,973.02 = 870.20 : x
2. Step 2: Convert to fraction form
   1,429.70/1,973.02 = 870.20/x
3. Step 3: Cross multiply
   1,429.70x = 1,973.02 × 870.20
4. Step 4: Simplify right side
   1,429.70x = 1,716,922.00
5. Step 5: Solve for x
   x = 1,716,922.00/1,429.70
6. Step 6: Final answer
   x = 1,200.90