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Finding the Fourth Proportional to 661.29, 991.22 and 290.76

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Solution

The fourth proportional to 661.29, 991.22 and 290.76 is: 435.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.29 : 991.22 = 290.76 : x
  2. Step 2: Convert to fraction form
    661.29/991.22 = 290.76/x
  3. Step 3: Cross multiply
    661.29x = 991.22 × 290.76
  4. Step 4: Simplify right side
    661.29x = 288,210.48
  5. Step 5: Solve for x
    x = 288,210.48/661.29
  6. Step 6: Final answer
    x = 435.83

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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.