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Finding the Fourth Proportional to 85.29, 117.66 and 71.42

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Solution

The fourth proportional to 85.29, 117.66 and 71.42 is: 98.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.29 : 117.66 = 71.42 : x
  2. Step 2: Convert to fraction form
    85.29/117.66 = 71.42/x
  3. Step 3: Cross multiply
    85.29x = 117.66 × 71.42
  4. Step 4: Simplify right side
    85.29x = 8,402.69
  5. Step 5: Solve for x
    x = 8,402.69/85.29
  6. Step 6: Final answer
    x = 98.52

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.