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Finding the Fourth Proportional to 419.67, 579.16 and 279.69

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Solution

The fourth proportional to 419.67, 579.16 and 279.69 is: 385.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.67 : 579.16 = 279.69 : x
  2. Step 2: Convert to fraction form
    419.67/579.16 = 279.69/x
  3. Step 3: Cross multiply
    419.67x = 579.16 × 279.69
  4. Step 4: Simplify right side
    419.67x = 161,987.78
  5. Step 5: Solve for x
    x = 161,987.78/419.67
  6. Step 6: Final answer
    x = 385.99

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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.