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Finding the Fourth Proportional to 72.58, 100.20 and 58.10

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Solution

The fourth proportional to 72.58, 100.20 and 58.10 is: 80.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.58 : 100.20 = 58.10 : x
  2. Step 2: Convert to fraction form
    72.58/100.20 = 58.10/x
  3. Step 3: Cross multiply
    72.58x = 100.20 × 58.10
  4. Step 4: Simplify right side
    72.58x = 5,821.62
  5. Step 5: Solve for x
    x = 5,821.62/72.58
  6. Step 6: Final answer
    x = 80.21

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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.