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Finding the Fourth Proportional to 669.65, 924.21 and 389.79

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Solution

The fourth proportional to 669.65, 924.21 and 389.79 is: 537.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.65 : 924.21 = 389.79 : x
  2. Step 2: Convert to fraction form
    669.65/924.21 = 389.79/x
  3. Step 3: Cross multiply
    669.65x = 924.21 × 389.79
  4. Step 4: Simplify right side
    669.65x = 360,247.82
  5. Step 5: Solve for x
    x = 360,247.82/669.65
  6. Step 6: Final answer
    x = 537.97

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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.