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Finding the Fourth Proportional to 665.40, 997.89 and 615.99

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Solution

The fourth proportional to 665.40, 997.89 and 615.99 is: 923.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.40 : 997.89 = 615.99 : x
  2. Step 2: Convert to fraction form
    665.40/997.89 = 615.99/x
  3. Step 3: Cross multiply
    665.40x = 997.89 × 615.99
  4. Step 4: Simplify right side
    665.40x = 614,690.26
  5. Step 5: Solve for x
    x = 614,690.26/665.40
  6. Step 6: Final answer
    x = 923.79

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.