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Finding the Fourth Proportional to 419.13, 578.55 and 279.35

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Solution

The fourth proportional to 419.13, 578.55 and 279.35 is: 385.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.13 : 578.55 = 279.35 : x
  2. Step 2: Convert to fraction form
    419.13/578.55 = 279.35/x
  3. Step 3: Cross multiply
    419.13x = 578.55 × 279.35
  4. Step 4: Simplify right side
    419.13x = 161,615.05
  5. Step 5: Solve for x
    x = 161,615.05/419.13
  6. Step 6: Final answer
    x = 385.60

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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.