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Finding the Fourth Proportional to 45.09, 67.87 and 40.90

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Solution

The fourth proportional to 45.09, 67.87 and 40.90 is: 61.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    45.09 : 67.87 = 40.90 : x
  2. Step 2: Convert to fraction form
    45.09/67.87 = 40.90/x
  3. Step 3: Cross multiply
    45.09x = 67.87 × 40.90
  4. Step 4: Simplify right side
    45.09x = 2,775.88
  5. Step 5: Solve for x
    x = 2,775.88/45.09
  6. Step 6: Final answer
    x = 61.56

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.