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Finding the Fourth Proportional to 390.39, 538.98 and 259.62

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Solution

The fourth proportional to 390.39, 538.98 and 259.62 is: 358.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.39 : 538.98 = 259.62 : x
  2. Step 2: Convert to fraction form
    390.39/538.98 = 259.62/x
  3. Step 3: Cross multiply
    390.39x = 538.98 × 259.62
  4. Step 4: Simplify right side
    390.39x = 139,929.99
  5. Step 5: Solve for x
    x = 139,929.99/390.39
  6. Step 6: Final answer
    x = 358.44

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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.