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Finding the Fourth Proportional to 616.80, 850.50 and 420.42

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Solution

The fourth proportional to 616.80, 850.50 and 420.42 is: 579.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    616.80 : 850.50 = 420.42 : x
  2. Step 2: Convert to fraction form
    616.80/850.50 = 420.42/x
  3. Step 3: Cross multiply
    616.80x = 850.50 × 420.42
  4. Step 4: Simplify right side
    616.80x = 357,567.21
  5. Step 5: Solve for x
    x = 357,567.21/616.80
  6. Step 6: Final answer
    x = 579.71

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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.