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Finding the Fourth Proportional to 665.62, 918.32 and 389.62

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Solution

The fourth proportional to 665.62, 918.32 and 389.62 is: 537.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.62 : 918.32 = 389.62 : x
  2. Step 2: Convert to fraction form
    665.62/918.32 = 389.62/x
  3. Step 3: Cross multiply
    665.62x = 918.32 × 389.62
  4. Step 4: Simplify right side
    665.62x = 357,795.84
  5. Step 5: Solve for x
    x = 357,795.84/665.62
  6. Step 6: Final answer
    x = 537.54

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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.