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Finding the Fourth Proportional to 419.92, 578.76 and 288.76

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Solution

The fourth proportional to 419.92, 578.76 and 288.76 is: 397.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.92 : 578.76 = 288.76 : x
  2. Step 2: Convert to fraction form
    419.92/578.76 = 288.76/x
  3. Step 3: Cross multiply
    419.92x = 578.76 × 288.76
  4. Step 4: Simplify right side
    419.92x = 167,122.74
  5. Step 5: Solve for x
    x = 167,122.74/419.92
  6. Step 6: Final answer
    x = 397.99

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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.