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Finding the Fourth Proportional to 419.63, 578.80 and 279.68

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Solution

The fourth proportional to 419.63, 578.80 and 279.68 is: 385.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.63 : 578.80 = 279.68 : x
  2. Step 2: Convert to fraction form
    419.63/578.80 = 279.68/x
  3. Step 3: Cross multiply
    419.63x = 578.80 × 279.68
  4. Step 4: Simplify right side
    419.63x = 161,876.29
  5. Step 5: Solve for x
    x = 161,876.29/419.63
  6. Step 6: Final answer
    x = 385.76

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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.