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Finding the Fourth Proportional to 142.88, 214.30 and 61.70

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Solution

The fourth proportional to 142.88, 214.30 and 61.70 is: 92.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    142.88 : 214.30 = 61.70 : x
  2. Step 2: Convert to fraction form
    142.88/214.30 = 61.70/x
  3. Step 3: Cross multiply
    142.88x = 214.30 × 61.70
  4. Step 4: Simplify right side
    142.88x = 13,221.87
  5. Step 5: Solve for x
    x = 13,221.87/142.88
  6. Step 6: Final answer
    x = 92.54

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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.