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Finding the Fourth Proportional to 380.39, 571.19 and 345.15

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Solution

The fourth proportional to 380.39, 571.19 and 345.15 is: 518.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.39 : 571.19 = 345.15 : x
  2. Step 2: Convert to fraction form
    380.39/571.19 = 345.15/x
  3. Step 3: Cross multiply
    380.39x = 571.19 × 345.15
  4. Step 4: Simplify right side
    380.39x = 197,144.50
  5. Step 5: Solve for x
    x = 197,144.50/380.39
  6. Step 6: Final answer
    x = 518.28

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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.