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Finding the Fourth Proportional to 142.72, 214.09 and 65.70

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Solution

The fourth proportional to 142.72, 214.09 and 65.70 is: 98.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    142.72 : 214.09 = 65.70 : x
  2. Step 2: Convert to fraction form
    142.72/214.09 = 65.70/x
  3. Step 3: Cross multiply
    142.72x = 214.09 × 65.70
  4. Step 4: Simplify right side
    142.72x = 14,065.71
  5. Step 5: Solve for x
    x = 14,065.71/142.72
  6. Step 6: Final answer
    x = 98.56

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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.