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Finding the Fourth Proportional to 390.00, 538.14 and 331.22

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Solution

The fourth proportional to 390.00, 538.14 and 331.22 is: 457.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.00 : 538.14 = 331.22 : x
  2. Step 2: Convert to fraction form
    390.00/538.14 = 331.22/x
  3. Step 3: Cross multiply
    390.00x = 538.14 × 331.22
  4. Step 4: Simplify right side
    390.00x = 178,245.32
  5. Step 5: Solve for x
    x = 178,245.32/390.00
  6. Step 6: Final answer
    x = 457.04

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.