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Finding the Fourth Proportional to 661.57, 992.19 and 199.21

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Solution

The fourth proportional to 661.57, 992.19 and 199.21 is: 298.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.57 : 992.19 = 199.21 : x
  2. Step 2: Convert to fraction form
    661.57/992.19 = 199.21/x
  3. Step 3: Cross multiply
    661.57x = 992.19 × 199.21
  4. Step 4: Simplify right side
    661.57x = 197,654.17
  5. Step 5: Solve for x
    x = 197,654.17/661.57
  6. Step 6: Final answer
    x = 298.77

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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.