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Finding the Fourth Proportional to 869.60, 1,304.94 and 407.90

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Solution

The fourth proportional to 869.60, 1,304.94 and 407.90 is: 612.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.60 : 1,304.94 = 407.90 : x
  2. Step 2: Convert to fraction form
    869.60/1,304.94 = 407.90/x
  3. Step 3: Cross multiply
    869.60x = 1,304.94 × 407.90
  4. Step 4: Simplify right side
    869.60x = 532,285.03
  5. Step 5: Solve for x
    x = 532,285.03/869.60
  6. Step 6: Final answer
    x = 612.10

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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.