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Finding the Fourth Proportional to 85.05, 117.35 and 58.80

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Solution

The fourth proportional to 85.05, 117.35 and 58.80 is: 81.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.05 : 117.35 = 58.80 : x
  2. Step 2: Convert to fraction form
    85.05/117.35 = 58.80/x
  3. Step 3: Cross multiply
    85.05x = 117.35 × 58.80
  4. Step 4: Simplify right side
    85.05x = 6,899.63
  5. Step 5: Solve for x
    x = 6,899.63/85.05
  6. Step 6: Final answer
    x = 81.12

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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.