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Finding the Fourth Proportional to 260.00, 389.72 and 86.50

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Solution

The fourth proportional to 260.00, 389.72 and 86.50 is: 129.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    260.00 : 389.72 = 86.50 : x
  2. Step 2: Convert to fraction form
    260.00/389.72 = 86.50/x
  3. Step 3: Cross multiply
    260.00x = 389.72 × 86.50
  4. Step 4: Simplify right side
    260.00x = 33,711.48
  5. Step 5: Solve for x
    x = 33,711.48/260.00
  6. Step 6: Final answer
    x = 129.66

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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.