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Finding the Fourth Proportional to 87.06, 120.17 and 64.89

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Solution

The fourth proportional to 87.06, 120.17 and 64.89 is: 89.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.06 : 120.17 = 64.89 : x
  2. Step 2: Convert to fraction form
    87.06/120.17 = 64.89/x
  3. Step 3: Cross multiply
    87.06x = 120.17 × 64.89
  4. Step 4: Simplify right side
    87.06x = 7,797.83
  5. Step 5: Solve for x
    x = 7,797.83/87.06
  6. Step 6: Final answer
    x = 89.57

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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.