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Finding the Fourth Proportional to 425.63, 638.64 and 407.57

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Solution

The fourth proportional to 425.63, 638.64 and 407.57 is: 611.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    425.63 : 638.64 = 407.57 : x
  2. Step 2: Convert to fraction form
    425.63/638.64 = 407.57/x
  3. Step 3: Cross multiply
    425.63x = 638.64 × 407.57
  4. Step 4: Simplify right side
    425.63x = 260,287.31
  5. Step 5: Solve for x
    x = 260,287.31/425.63
  6. Step 6: Final answer
    x = 611.54

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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.