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Finding the Fourth Proportional to 419.86, 579.11 and 279.91

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Solution

The fourth proportional to 419.86, 579.11 and 279.91 is: 386.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.86 : 579.11 = 279.91 : x
  2. Step 2: Convert to fraction form
    419.86/579.11 = 279.91/x
  3. Step 3: Cross multiply
    419.86x = 579.11 × 279.91
  4. Step 4: Simplify right side
    419.86x = 162,098.68
  5. Step 5: Solve for x
    x = 162,098.68/419.86
  6. Step 6: Final answer
    x = 386.08

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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.