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Finding the Fourth Proportional to 85.85, 129.49 and 85.85

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Solution

The fourth proportional to 85.85, 129.49 and 85.85 is: 129.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.85 : 129.49 = 85.85 : x
  2. Step 2: Convert to fraction form
    85.85/129.49 = 85.85/x
  3. Step 3: Cross multiply
    85.85x = 129.49 × 85.85
  4. Step 4: Simplify right side
    85.85x = 11,116.72
  5. Step 5: Solve for x
    x = 11,116.72/85.85
  6. Step 6: Final answer
    x = 129.49

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.