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Finding the Fourth Proportional to 868.20, 1,302.12 and 381.12

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Solution

The fourth proportional to 868.20, 1,302.12 and 381.12 is: 571.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    868.20 : 1,302.12 = 381.12 : x
  2. Step 2: Convert to fraction form
    868.20/1,302.12 = 381.12/x
  3. Step 3: Cross multiply
    868.20x = 1,302.12 × 381.12
  4. Step 4: Simplify right side
    868.20x = 496,263.97
  5. Step 5: Solve for x
    x = 496,263.97/868.20
  6. Step 6: Final answer
    x = 571.60

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1.5x scale

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.