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Finding the Fourth Proportional to 145.48, 217.12 and 138.20

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Solution

The fourth proportional to 145.48, 217.12 and 138.20 is: 206.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.48 : 217.12 = 138.20 : x
  2. Step 2: Convert to fraction form
    145.48/217.12 = 138.20/x
  3. Step 3: Cross multiply
    145.48x = 217.12 × 138.20
  4. Step 4: Simplify right side
    145.48x = 30,005.98
  5. Step 5: Solve for x
    x = 30,005.98/145.48
  6. Step 6: Final answer
    x = 206.26

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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.