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Finding the Fourth Proportional to 390.60, 537.97 and 307.58

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Solution

The fourth proportional to 390.60, 537.97 and 307.58 is: 423.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.60 : 537.97 = 307.58 : x
  2. Step 2: Convert to fraction form
    390.60/537.97 = 307.58/x
  3. Step 3: Cross multiply
    390.60x = 537.97 × 307.58
  4. Step 4: Simplify right side
    390.60x = 165,468.81
  5. Step 5: Solve for x
    x = 165,468.81/390.60
  6. Step 6: Final answer
    x = 423.63

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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.