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Finding the Fourth Proportional to 288.71, 395.87 and 285.06

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Solution

The fourth proportional to 288.71, 395.87 and 285.06 is: 390.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.71 : 395.87 = 285.06 : x
  2. Step 2: Convert to fraction form
    288.71/395.87 = 285.06/x
  3. Step 3: Cross multiply
    288.71x = 395.87 × 285.06
  4. Step 4: Simplify right side
    288.71x = 112,847.41
  5. Step 5: Solve for x
    x = 112,847.41/288.71
  6. Step 6: Final answer
    x = 390.87

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.