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Finding the Fourth Proportional to 390.18, 538.55 and 240.86

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Solution

The fourth proportional to 390.18, 538.55 and 240.86 is: 332.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.18 : 538.55 = 240.86 : x
  2. Step 2: Convert to fraction form
    390.18/538.55 = 240.86/x
  3. Step 3: Cross multiply
    390.18x = 538.55 × 240.86
  4. Step 4: Simplify right side
    390.18x = 129,711.26
  5. Step 5: Solve for x
    x = 129,711.26/390.18
  6. Step 6: Final answer
    x = 332.44

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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.