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Finding the Fourth Proportional to 639.40, 952.29 and 616.72

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Solution

The fourth proportional to 639.40, 952.29 and 616.72 is: 918.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.40 : 952.29 = 616.72 : x
  2. Step 2: Convert to fraction form
    639.40/952.29 = 616.72/x
  3. Step 3: Cross multiply
    639.40x = 952.29 × 616.72
  4. Step 4: Simplify right side
    639.40x = 587,296.29
  5. Step 5: Solve for x
    x = 587,296.29/639.40
  6. Step 6: Final answer
    x = 918.51

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.