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Finding the Fourth Proportional to 287.08, 431.28 and 178.90

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Solution

The fourth proportional to 287.08, 431.28 and 178.90 is: 268.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.08 : 431.28 = 178.90 : x
  2. Step 2: Convert to fraction form
    287.08/431.28 = 178.90/x
  3. Step 3: Cross multiply
    287.08x = 431.28 × 178.90
  4. Step 4: Simplify right side
    287.08x = 77,155.99
  5. Step 5: Solve for x
    x = 77,155.99/287.08
  6. Step 6: Final answer
    x = 268.76

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.