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Finding the Fourth Proportional to 670.30, 925.02 and 390.64

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Solution

The fourth proportional to 670.30, 925.02 and 390.64 is: 539.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    670.30 : 925.02 = 390.64 : x
  2. Step 2: Convert to fraction form
    670.30/925.02 = 390.64/x
  3. Step 3: Cross multiply
    670.30x = 925.02 × 390.64
  4. Step 4: Simplify right side
    670.30x = 361,349.81
  5. Step 5: Solve for x
    x = 361,349.81/670.30
  6. Step 6: Final answer
    x = 539.09

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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.