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Finding the Fourth Proportional to 287.60, 396.96 and 171.20

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Solution

The fourth proportional to 287.60, 396.96 and 171.20 is: 236.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.60 : 396.96 = 171.20 : x
  2. Step 2: Convert to fraction form
    287.60/396.96 = 171.20/x
  3. Step 3: Cross multiply
    287.60x = 396.96 × 171.20
  4. Step 4: Simplify right side
    287.60x = 67,959.55
  5. Step 5: Solve for x
    x = 67,959.55/287.60
  6. Step 6: Final answer
    x = 236.30

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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.