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Finding the Fourth Proportional to 393.59, 542.47 and 288.65

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Solution

The fourth proportional to 393.59, 542.47 and 288.65 is: 397.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    393.59 : 542.47 = 288.65 : x
  2. Step 2: Convert to fraction form
    393.59/542.47 = 288.65/x
  3. Step 3: Cross multiply
    393.59x = 542.47 × 288.65
  4. Step 4: Simplify right side
    393.59x = 156,583.97
  5. Step 5: Solve for x
    x = 156,583.97/393.59
  6. Step 6: Final answer
    x = 397.84

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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.