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Finding the Fourth Proportional to 418.96, 578.40 and 288.16

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Solution

The fourth proportional to 418.96, 578.40 and 288.16 is: 397.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.96 : 578.40 = 288.16 : x
  2. Step 2: Convert to fraction form
    418.96/578.40 = 288.16/x
  3. Step 3: Cross multiply
    418.96x = 578.40 × 288.16
  4. Step 4: Simplify right side
    418.96x = 166,671.74
  5. Step 5: Solve for x
    x = 166,671.74/418.96
  6. Step 6: Final answer
    x = 397.82

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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.