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Finding the Fourth Proportional to 669.86, 924.41 and 390.29

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Solution

The fourth proportional to 669.86, 924.41 and 390.29 is: 538.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.86 : 924.41 = 390.29 : x
  2. Step 2: Convert to fraction form
    669.86/924.41 = 390.29/x
  3. Step 3: Cross multiply
    669.86x = 924.41 × 390.29
  4. Step 4: Simplify right side
    669.86x = 360,788.78
  5. Step 5: Solve for x
    x = 360,788.78/669.86
  6. Step 6: Final answer
    x = 538.60

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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.