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Finding the Fourth Proportional to 287.78, 397.10 and 169.72

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Solution

The fourth proportional to 287.78, 397.10 and 169.72 is: 234.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.78 : 397.10 = 169.72 : x
  2. Step 2: Convert to fraction form
    287.78/397.10 = 169.72/x
  3. Step 3: Cross multiply
    287.78x = 397.10 × 169.72
  4. Step 4: Simplify right side
    287.78x = 67,395.81
  5. Step 5: Solve for x
    x = 67,395.81/287.78
  6. Step 6: Final answer
    x = 234.19

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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.