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Finding the Fourth Proportional to 380.72, 571.08 and 259.28

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Solution

The fourth proportional to 380.72, 571.08 and 259.28 is: 388.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.72 : 571.08 = 259.28 : x
  2. Step 2: Convert to fraction form
    380.72/571.08 = 259.28/x
  3. Step 3: Cross multiply
    380.72x = 571.08 × 259.28
  4. Step 4: Simplify right side
    380.72x = 148,069.62
  5. Step 5: Solve for x
    x = 148,069.62/380.72
  6. Step 6: Final answer
    x = 388.92

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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.