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Finding the Fourth Proportional to 806.76, 1,209.89 and 513.84

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Solution

The fourth proportional to 806.76, 1,209.89 and 513.84 is: 770.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.76 : 1,209.89 = 513.84 : x
  2. Step 2: Convert to fraction form
    806.76/1,209.89 = 513.84/x
  3. Step 3: Cross multiply
    806.76x = 1,209.89 × 513.84
  4. Step 4: Simplify right side
    806.76x = 621,692.81
  5. Step 5: Solve for x
    x = 621,692.81/806.76
  6. Step 6: Final answer
    x = 770.60

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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.