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Finding the Fourth Proportional to 142.85, 214.31 and 70.69

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Solution

The fourth proportional to 142.85, 214.31 and 70.69 is: 106.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    142.85 : 214.31 = 70.69 : x
  2. Step 2: Convert to fraction form
    142.85/214.31 = 70.69/x
  3. Step 3: Cross multiply
    142.85x = 214.31 × 70.69
  4. Step 4: Simplify right side
    142.85x = 15,149.57
  5. Step 5: Solve for x
    x = 15,149.57/142.85
  6. Step 6: Final answer
    x = 106.05

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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.