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Finding the Fourth Proportional to 144.69, 215.87 and 128.69

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Solution

The fourth proportional to 144.69, 215.87 and 128.69 is: 192.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    144.69 : 215.87 = 128.69 : x
  2. Step 2: Convert to fraction form
    144.69/215.87 = 128.69/x
  3. Step 3: Cross multiply
    144.69x = 215.87 × 128.69
  4. Step 4: Simplify right side
    144.69x = 27,779.40
  5. Step 5: Solve for x
    x = 27,779.40/144.69
  6. Step 6: Final answer
    x = 192.00

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.