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Finding the Fourth Proportional to 145.20, 217.78 and 68.14

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Solution

The fourth proportional to 145.20, 217.78 and 68.14 is: 102.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.20 : 217.78 = 68.14 : x
  2. Step 2: Convert to fraction form
    145.20/217.78 = 68.14/x
  3. Step 3: Cross multiply
    145.20x = 217.78 × 68.14
  4. Step 4: Simplify right side
    145.20x = 14,839.53
  5. Step 5: Solve for x
    x = 14,839.53/145.20
  6. Step 6: Final answer
    x = 102.20

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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.