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Finding the Fourth Proportional to 661.20, 991.82 and 290.82

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Solution

The fourth proportional to 661.20, 991.82 and 290.82 is: 436.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.20 : 991.82 = 290.82 : x
  2. Step 2: Convert to fraction form
    661.20/991.82 = 290.82/x
  3. Step 3: Cross multiply
    661.20x = 991.82 × 290.82
  4. Step 4: Simplify right side
    661.20x = 288,437.84
  5. Step 5: Solve for x
    x = 288,437.84/661.20
  6. Step 6: Final answer
    x = 436.23

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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.