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Finding the Fourth Proportional to 66.85, 99.79 and 58.75

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Solution

The fourth proportional to 66.85, 99.79 and 58.75 is: 87.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.85 : 99.79 = 58.75 : x
  2. Step 2: Convert to fraction form
    66.85/99.79 = 58.75/x
  3. Step 3: Cross multiply
    66.85x = 99.79 × 58.75
  4. Step 4: Simplify right side
    66.85x = 5,862.66
  5. Step 5: Solve for x
    x = 5,862.66/66.85
  6. Step 6: Final answer
    x = 87.70

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.