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Finding the Fourth Proportional to 87.23, 130.66 and 56.81

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Solution

The fourth proportional to 87.23, 130.66 and 56.81 is: 85.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.23 : 130.66 = 56.81 : x
  2. Step 2: Convert to fraction form
    87.23/130.66 = 56.81/x
  3. Step 3: Cross multiply
    87.23x = 130.66 × 56.81
  4. Step 4: Simplify right side
    87.23x = 7,422.79
  5. Step 5: Solve for x
    x = 7,422.79/87.23
  6. Step 6: Final answer
    x = 85.09

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.