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Finding the Fourth Proportional to 805.11, 1,206.80 and 342.81

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Solution

The fourth proportional to 805.11, 1,206.80 and 342.81 is: 513.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.11 : 1,206.80 = 342.81 : x
  2. Step 2: Convert to fraction form
    805.11/1,206.80 = 342.81/x
  3. Step 3: Cross multiply
    805.11x = 1,206.80 × 342.81
  4. Step 4: Simplify right side
    805.11x = 413,701.39
  5. Step 5: Solve for x
    x = 413,701.39/805.11
  6. Step 6: Final answer
    x = 513.84

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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.