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Finding the Fourth Proportional to 58.15, 80.21 and 39.74

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Solution

The fourth proportional to 58.15, 80.21 and 39.74 is: 54.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    58.15 : 80.21 = 39.74 : x
  2. Step 2: Convert to fraction form
    58.15/80.21 = 39.74/x
  3. Step 3: Cross multiply
    58.15x = 80.21 × 39.74
  4. Step 4: Simplify right side
    58.15x = 3,187.55
  5. Step 5: Solve for x
    x = 3,187.55/58.15
  6. Step 6: Final answer
    x = 54.82

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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.