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Finding the Fourth Proportional to 55.80, 77 and 47.60

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Solution

The fourth proportional to 55.80, 77 and 47.60 is: 65.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.80 : 77 = 47.60 : x
  2. Step 2: Convert to fraction form
    55.80/77 = 47.60/x
  3. Step 3: Cross multiply
    55.80x = 77 × 47.60
  4. Step 4: Simplify right side
    55.80x = 3,665.20
  5. Step 5: Solve for x
    x = 3,665.20/55.80
  6. Step 6: Final answer
    x = 65.68

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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.