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Finding the Fourth Proportional to 805.10, 1,206.65 and 342.50

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Solution

The fourth proportional to 805.10, 1,206.65 and 342.50 is: 513.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.10 : 1,206.65 = 342.50 : x
  2. Step 2: Convert to fraction form
    805.10/1,206.65 = 342.50/x
  3. Step 3: Cross multiply
    805.10x = 1,206.65 × 342.50
  4. Step 4: Simplify right side
    805.10x = 413,269.88
  5. Step 5: Solve for x
    x = 413,269.88/805.10
  6. Step 6: Final answer
    x = 513.32

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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.