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Finding the Fourth Proportional to 390.29, 538.10 and 323.66

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Solution

The fourth proportional to 390.29, 538.10 and 323.66 is: 446.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.29 : 538.10 = 323.66 : x
  2. Step 2: Convert to fraction form
    390.29/538.10 = 323.66/x
  3. Step 3: Cross multiply
    390.29x = 538.10 × 323.66
  4. Step 4: Simplify right side
    390.29x = 174,161.17
  5. Step 5: Solve for x
    x = 174,161.17/390.29
  6. Step 6: Final answer
    x = 446.23

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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.