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Finding the Fourth Proportional to 665.68, 998.45 and 178.78

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Solution

The fourth proportional to 665.68, 998.45 and 178.78 is: 268.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.68 : 998.45 = 178.78 : x
  2. Step 2: Convert to fraction form
    665.68/998.45 = 178.78/x
  3. Step 3: Cross multiply
    665.68x = 998.45 × 178.78
  4. Step 4: Simplify right side
    665.68x = 178,502.89
  5. Step 5: Solve for x
    x = 178,502.89/665.68
  6. Step 6: Final answer
    x = 268.15

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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.