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Finding the Fourth Proportional to 665.57, 918.79 and 499.52

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Solution

The fourth proportional to 665.57, 918.79 and 499.52 is: 689.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.57 : 918.79 = 499.52 : x
  2. Step 2: Convert to fraction form
    665.57/918.79 = 499.52/x
  3. Step 3: Cross multiply
    665.57x = 918.79 × 499.52
  4. Step 4: Simplify right side
    665.57x = 458,952.67
  5. Step 5: Solve for x
    x = 458,952.67/665.57
  6. Step 6: Final answer
    x = 689.57

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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.