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Finding the Fourth Proportional to 61.40, 84.76 and 40.71

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Solution

The fourth proportional to 61.40, 84.76 and 40.71 is: 56.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    61.40 : 84.76 = 40.71 : x
  2. Step 2: Convert to fraction form
    61.40/84.76 = 40.71/x
  3. Step 3: Cross multiply
    61.40x = 84.76 × 40.71
  4. Step 4: Simplify right side
    61.40x = 3,450.79
  5. Step 5: Solve for x
    x = 3,450.79/61.40
  6. Step 6: Final answer
    x = 56.20

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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.