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Finding the Fourth Proportional to 419.75, 578.68 and 279.87

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Solution

The fourth proportional to 419.75, 578.68 and 279.87 is: 385.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.75 : 578.68 = 279.87 : x
  2. Step 2: Convert to fraction form
    419.75/578.68 = 279.87/x
  3. Step 3: Cross multiply
    419.75x = 578.68 × 279.87
  4. Step 4: Simplify right side
    419.75x = 161,955.17
  5. Step 5: Solve for x
    x = 161,955.17/419.75
  6. Step 6: Final answer
    x = 385.84

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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.