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Finding the Fourth Proportional to 869.80, 1,304.85 and 407.47

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Solution

The fourth proportional to 869.80, 1,304.85 and 407.47 is: 611.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.80 : 1,304.85 = 407.47 : x
  2. Step 2: Convert to fraction form
    869.80/1,304.85 = 407.47/x
  3. Step 3: Cross multiply
    869.80x = 1,304.85 × 407.47
  4. Step 4: Simplify right side
    869.80x = 531,687.23
  5. Step 5: Solve for x
    x = 531,687.23/869.80
  6. Step 6: Final answer
    x = 611.28

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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.