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Finding the Fourth Proportional to 661.86, 991.98 and 353.79

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Solution

The fourth proportional to 661.86, 991.98 and 353.79 is: 530.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.86 : 991.98 = 353.79 : x
  2. Step 2: Convert to fraction form
    661.86/991.98 = 353.79/x
  3. Step 3: Cross multiply
    661.86x = 991.98 × 353.79
  4. Step 4: Simplify right side
    661.86x = 350,952.60
  5. Step 5: Solve for x
    x = 350,952.60/661.86
  6. Step 6: Final answer
    x = 530.25

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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.