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Finding the Fourth Proportional to 87.00, 120.02 and 53.79

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Solution

The fourth proportional to 87.00, 120.02 and 53.79 is: 74.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.00 : 120.02 = 53.79 : x
  2. Step 2: Convert to fraction form
    87.00/120.02 = 53.79/x
  3. Step 3: Cross multiply
    87.00x = 120.02 × 53.79
  4. Step 4: Simplify right side
    87.00x = 6,456.23
  5. Step 5: Solve for x
    x = 6,456.23/87.00
  6. Step 6: Final answer
    x = 74.21

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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.