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Finding the Fourth Proportional to 419.79, 578.61 and 288.57

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Solution

The fourth proportional to 419.79, 578.61 and 288.57 is: 397.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.79 : 578.61 = 288.57 : x
  2. Step 2: Convert to fraction form
    419.79/578.61 = 288.57/x
  3. Step 3: Cross multiply
    419.79x = 578.61 × 288.57
  4. Step 4: Simplify right side
    419.79x = 166,969.49
  5. Step 5: Solve for x
    x = 166,969.49/419.79
  6. Step 6: Final answer
    x = 397.75

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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.