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Finding the Fourth Proportional to 623.20, 860.16 and 387.28

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Solution

The fourth proportional to 623.20, 860.16 and 387.28 is: 534.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    623.20 : 860.16 = 387.28 : x
  2. Step 2: Convert to fraction form
    623.20/860.16 = 387.28/x
  3. Step 3: Cross multiply
    623.20x = 860.16 × 387.28
  4. Step 4: Simplify right side
    623.20x = 333,122.76
  5. Step 5: Solve for x
    x = 333,122.76/623.20
  6. Step 6: Final answer
    x = 534.54

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.