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Finding the Fourth Proportional to 858.94, 1,288.41 and 209.67

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Solution

The fourth proportional to 858.94, 1,288.41 and 209.67 is: 314.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    858.94 : 1,288.41 = 209.67 : x
  2. Step 2: Convert to fraction form
    858.94/1,288.41 = 209.67/x
  3. Step 3: Cross multiply
    858.94x = 1,288.41 × 209.67
  4. Step 4: Simplify right side
    858.94x = 270,142.55
  5. Step 5: Solve for x
    x = 270,142.55/858.94
  6. Step 6: Final answer
    x = 314.51

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.