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Finding the Fourth Proportional to 638.95, 959.06 and 430.69

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Solution

The fourth proportional to 638.95, 959.06 and 430.69 is: 646.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.95 : 959.06 = 430.69 : x
  2. Step 2: Convert to fraction form
    638.95/959.06 = 430.69/x
  3. Step 3: Cross multiply
    638.95x = 959.06 × 430.69
  4. Step 4: Simplify right side
    638.95x = 413,057.55
  5. Step 5: Solve for x
    x = 413,057.55/638.95
  6. Step 6: Final answer
    x = 646.46

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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.