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Finding the Fourth Proportional to 661.23, 991.49 and 401.36

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Solution

The fourth proportional to 661.23, 991.49 and 401.36 is: 601.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.23 : 991.49 = 401.36 : x
  2. Step 2: Convert to fraction form
    661.23/991.49 = 401.36/x
  3. Step 3: Cross multiply
    661.23x = 991.49 × 401.36
  4. Step 4: Simplify right side
    661.23x = 397,937.46
  5. Step 5: Solve for x
    x = 397,937.46/661.23
  6. Step 6: Final answer
    x = 601.81

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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.