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Finding the Fourth Proportional to 387.20, 580.80 and 170.84

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Solution

The fourth proportional to 387.20, 580.80 and 170.84 is: 256.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.20 : 580.80 = 170.84 : x
  2. Step 2: Convert to fraction form
    387.20/580.80 = 170.84/x
  3. Step 3: Cross multiply
    387.20x = 580.80 × 170.84
  4. Step 4: Simplify right side
    387.20x = 99,223.87
  5. Step 5: Solve for x
    x = 99,223.87/387.20
  6. Step 6: Final answer
    x = 256.26

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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.