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Finding the Fourth Proportional to 57.47, 79.28 and 39.05

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Solution

The fourth proportional to 57.47, 79.28 and 39.05 is: 53.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    57.47 : 79.28 = 39.05 : x
  2. Step 2: Convert to fraction form
    57.47/79.28 = 39.05/x
  3. Step 3: Cross multiply
    57.47x = 79.28 × 39.05
  4. Step 4: Simplify right side
    57.47x = 3,095.49
  5. Step 5: Solve for x
    x = 3,095.49/57.47
  6. Step 6: Final answer
    x = 53.86

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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.