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Finding the Fourth Proportional to 108.57, 162.47 and 85.58

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Solution

The fourth proportional to 108.57, 162.47 and 85.58 is: 128.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.57 : 162.47 = 85.58 : x
  2. Step 2: Convert to fraction form
    108.57/162.47 = 85.58/x
  3. Step 3: Cross multiply
    108.57x = 162.47 × 85.58
  4. Step 4: Simplify right side
    108.57x = 13,904.18
  5. Step 5: Solve for x
    x = 13,904.18/108.57
  6. Step 6: Final answer
    x = 128.07

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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.