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Finding the Fourth Proportional to 39.99, 55.18 and 38.58

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Solution

The fourth proportional to 39.99, 55.18 and 38.58 is: 53.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    39.99 : 55.18 = 38.58 : x
  2. Step 2: Convert to fraction form
    39.99/55.18 = 38.58/x
  3. Step 3: Cross multiply
    39.99x = 55.18 × 38.58
  4. Step 4: Simplify right side
    39.99x = 2,128.69
  5. Step 5: Solve for x
    x = 2,128.69/39.99
  6. Step 6: Final answer
    x = 53.23

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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.