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Finding the Fourth Proportional to 639.80, 960.50 and 610.38

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Solution

The fourth proportional to 639.80, 960.50 and 610.38 is: 916.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.80 : 960.50 = 610.38 : x
  2. Step 2: Convert to fraction form
    639.80/960.50 = 610.38/x
  3. Step 3: Cross multiply
    639.80x = 960.50 × 610.38
  4. Step 4: Simplify right side
    639.80x = 586,269.99
  5. Step 5: Solve for x
    x = 586,269.99/639.80
  6. Step 6: Final answer
    x = 916.33

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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.