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Finding the Fourth Proportional to 81.40, 112.19 and 58.10

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Solution

The fourth proportional to 81.40, 112.19 and 58.10 is: 80.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    81.40 : 112.19 = 58.10 : x
  2. Step 2: Convert to fraction form
    81.40/112.19 = 58.10/x
  3. Step 3: Cross multiply
    81.40x = 112.19 × 58.10
  4. Step 4: Simplify right side
    81.40x = 6,518.24
  5. Step 5: Solve for x
    x = 6,518.24/81.40
  6. Step 6: Final answer
    x = 80.08

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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.