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Finding the Fourth Proportional to 259.38, 388.64 and 143.64

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Solution

The fourth proportional to 259.38, 388.64 and 143.64 is: 215.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    259.38 : 388.64 = 143.64 : x
  2. Step 2: Convert to fraction form
    259.38/388.64 = 143.64/x
  3. Step 3: Cross multiply
    259.38x = 388.64 × 143.64
  4. Step 4: Simplify right side
    259.38x = 55,824.25
  5. Step 5: Solve for x
    x = 55,824.25/259.38
  6. Step 6: Final answer
    x = 215.22

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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.