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Finding the Fourth Proportional to 57.20, 85.70 and 48.60

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Solution

The fourth proportional to 57.20, 85.70 and 48.60 is: 72.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    57.20 : 85.70 = 48.60 : x
  2. Step 2: Convert to fraction form
    57.20/85.70 = 48.60/x
  3. Step 3: Cross multiply
    57.20x = 85.70 × 48.60
  4. Step 4: Simplify right side
    57.20x = 4,165.02
  5. Step 5: Solve for x
    x = 4,165.02/57.20
  6. Step 6: Final answer
    x = 72.82

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.