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Finding the Fourth Proportional to 380.79, 571.46 and 218.79

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Solution

The fourth proportional to 380.79, 571.46 and 218.79 is: 328.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.79 : 571.46 = 218.79 : x
  2. Step 2: Convert to fraction form
    380.79/571.46 = 218.79/x
  3. Step 3: Cross multiply
    380.79x = 571.46 × 218.79
  4. Step 4: Simplify right side
    380.79x = 125,028.64
  5. Step 5: Solve for x
    x = 125,028.64/380.79
  6. Step 6: Final answer
    x = 328.34

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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.