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Finding the Fourth Proportional to 65.80, 98.61 and 53.65

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Solution

The fourth proportional to 65.80, 98.61 and 53.65 is: 80.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.80 : 98.61 = 53.65 : x
  2. Step 2: Convert to fraction form
    65.80/98.61 = 53.65/x
  3. Step 3: Cross multiply
    65.80x = 98.61 × 53.65
  4. Step 4: Simplify right side
    65.80x = 5,289.93
  5. Step 5: Solve for x
    x = 5,289.93/65.80
  6. Step 6: Final answer
    x = 80.39

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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.