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Finding the Fourth Proportional to 65.80, 90.77 and 42.47

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Solution

The fourth proportional to 65.80, 90.77 and 42.47 is: 58.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.80 : 90.77 = 42.47 : x
  2. Step 2: Convert to fraction form
    65.80/90.77 = 42.47/x
  3. Step 3: Cross multiply
    65.80x = 90.77 × 42.47
  4. Step 4: Simplify right side
    65.80x = 3,855.00
  5. Step 5: Solve for x
    x = 3,855.00/65.80
  6. Step 6: Final answer
    x = 58.59

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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.