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Finding the Fourth Proportional to 145.29, 217.65 and 139.65

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Solution

The fourth proportional to 145.29, 217.65 and 139.65 is: 209.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.29 : 217.65 = 139.65 : x
  2. Step 2: Convert to fraction form
    145.29/217.65 = 139.65/x
  3. Step 3: Cross multiply
    145.29x = 217.65 × 139.65
  4. Step 4: Simplify right side
    145.29x = 30,394.82
  5. Step 5: Solve for x
    x = 30,394.82/145.29
  6. Step 6: Final answer
    x = 209.20

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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.