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Finding the Fourth Proportional to 61.81, 85.25 and 40.79

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Solution

The fourth proportional to 61.81, 85.25 and 40.79 is: 56.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    61.81 : 85.25 = 40.79 : x
  2. Step 2: Convert to fraction form
    61.81/85.25 = 40.79/x
  3. Step 3: Cross multiply
    61.81x = 85.25 × 40.79
  4. Step 4: Simplify right side
    61.81x = 3,477.66
  5. Step 5: Solve for x
    x = 3,477.66/61.81
  6. Step 6: Final answer
    x = 56.27

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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.