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Finding the Fourth Proportional to 617.48, 850.79 and 420.65

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Solution

The fourth proportional to 617.48, 850.79 and 420.65 is: 579.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    617.48 : 850.79 = 420.65 : x
  2. Step 2: Convert to fraction form
    617.48/850.79 = 420.65/x
  3. Step 3: Cross multiply
    617.48x = 850.79 × 420.65
  4. Step 4: Simplify right side
    617.48x = 357,884.81
  5. Step 5: Solve for x
    x = 357,884.81/617.48
  6. Step 6: Final answer
    x = 579.59

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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.