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Finding the Fourth Proportional to 145.38, 200.52 and 128.91

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Solution

The fourth proportional to 145.38, 200.52 and 128.91 is: 177.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.38 : 200.52 = 128.91 : x
  2. Step 2: Convert to fraction form
    145.38/200.52 = 128.91/x
  3. Step 3: Cross multiply
    145.38x = 200.52 × 128.91
  4. Step 4: Simplify right side
    145.38x = 25,849.03
  5. Step 5: Solve for x
    x = 25,849.03/145.38
  6. Step 6: Final answer
    x = 177.80

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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.