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Finding the Fourth Proportional to 661.65, 913.08 and 381.96

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Solution

The fourth proportional to 661.65, 913.08 and 381.96 is: 527.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.65 : 913.08 = 381.96 : x
  2. Step 2: Convert to fraction form
    661.65/913.08 = 381.96/x
  3. Step 3: Cross multiply
    661.65x = 913.08 × 381.96
  4. Step 4: Simplify right side
    661.65x = 348,760.04
  5. Step 5: Solve for x
    x = 348,760.04/661.65
  6. Step 6: Final answer
    x = 527.11

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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.