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Finding the Fourth Proportional to 869.98, 1,305.18 and 285.10

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Solution

The fourth proportional to 869.98, 1,305.18 and 285.10 is: 427.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.98 : 1,305.18 = 285.10 : x
  2. Step 2: Convert to fraction form
    869.98/1,305.18 = 285.10/x
  3. Step 3: Cross multiply
    869.98x = 1,305.18 × 285.10
  4. Step 4: Simplify right side
    869.98x = 372,106.82
  5. Step 5: Solve for x
    x = 372,106.82/869.98
  6. Step 6: Final answer
    x = 427.72

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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.