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Finding the Fourth Proportional to 288.72, 398.40 and 170.70

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Solution

The fourth proportional to 288.72, 398.40 and 170.70 is: 235.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.72 : 398.40 = 170.70 : x
  2. Step 2: Convert to fraction form
    288.72/398.40 = 170.70/x
  3. Step 3: Cross multiply
    288.72x = 398.40 × 170.70
  4. Step 4: Simplify right side
    288.72x = 68,006.88
  5. Step 5: Solve for x
    x = 68,006.88/288.72
  6. Step 6: Final answer
    x = 235.55

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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.