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Finding the Fourth Proportional to 87.54, 130.58 and 86.19

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Solution

The fourth proportional to 87.54, 130.58 and 86.19 is: 128.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.54 : 130.58 = 86.19 : x
  2. Step 2: Convert to fraction form
    87.54/130.58 = 86.19/x
  3. Step 3: Cross multiply
    87.54x = 130.58 × 86.19
  4. Step 4: Simplify right side
    87.54x = 11,254.26
  5. Step 5: Solve for x
    x = 11,254.26/87.54
  6. Step 6: Final answer
    x = 128.56

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.