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Finding the Fourth Proportional to 108.60, 162.90 and 47.70

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Solution

The fourth proportional to 108.60, 162.90 and 47.70 is: 71.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.60 : 162.90 = 47.70 : x
  2. Step 2: Convert to fraction form
    108.60/162.90 = 47.70/x
  3. Step 3: Cross multiply
    108.60x = 162.90 × 47.70
  4. Step 4: Simplify right side
    108.60x = 7,770.33
  5. Step 5: Solve for x
    x = 7,770.33/108.60
  6. Step 6: Final answer
    x = 71.55

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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.