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Finding the Fourth Proportional to 85.34, 117.72 and 71.71

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Solution

The fourth proportional to 85.34, 117.72 and 71.71 is: 98.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.34 : 117.72 = 71.71 : x
  2. Step 2: Convert to fraction form
    85.34/117.72 = 71.71/x
  3. Step 3: Cross multiply
    85.34x = 117.72 × 71.71
  4. Step 4: Simplify right side
    85.34x = 8,441.41
  5. Step 5: Solve for x
    x = 8,441.41/85.34
  6. Step 6: Final answer
    x = 98.91

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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.