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Finding the Fourth Proportional to 71.81, 99.09 and 40.71

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Solution

The fourth proportional to 71.81, 99.09 and 40.71 is: 56.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.81 : 99.09 = 40.71 : x
  2. Step 2: Convert to fraction form
    71.81/99.09 = 40.71/x
  3. Step 3: Cross multiply
    71.81x = 99.09 × 40.71
  4. Step 4: Simplify right side
    71.81x = 4,033.95
  5. Step 5: Solve for x
    x = 4,033.95/71.81
  6. Step 6: Final answer
    x = 56.18

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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.