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Finding the Fourth Proportional to 39.28, 53.84 and 38.80

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Solution

The fourth proportional to 39.28, 53.84 and 38.80 is: 53.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    39.28 : 53.84 = 38.80 : x
  2. Step 2: Convert to fraction form
    39.28/53.84 = 38.80/x
  3. Step 3: Cross multiply
    39.28x = 53.84 × 38.80
  4. Step 4: Simplify right side
    39.28x = 2,088.99
  5. Step 5: Solve for x
    x = 2,088.99/39.28
  6. Step 6: Final answer
    x = 53.18

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.