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Finding the Fourth Proportional to 869.85, 1,305.62 and 407.94

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Solution

The fourth proportional to 869.85, 1,305.62 and 407.94 is: 612.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.85 : 1,305.62 = 407.94 : x
  2. Step 2: Convert to fraction form
    869.85/1,305.62 = 407.94/x
  3. Step 3: Cross multiply
    869.85x = 1,305.62 × 407.94
  4. Step 4: Simplify right side
    869.85x = 532,612.58
  5. Step 5: Solve for x
    x = 532,612.58/869.85
  6. Step 6: Final answer
    x = 612.30

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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.