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Finding the Fourth Proportional to 1,209, 1,813.50 and 439.68

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Solution

The fourth proportional to 1,209, 1,813.50 and 439.68 is: 659.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,209 : 1,813.50 = 439.68 : x
  2. Step 2: Convert to fraction form
    1,209/1,813.50 = 439.68/x
  3. Step 3: Cross multiply
    1,209x = 1,813.50 × 439.68
  4. Step 4: Simplify right side
    1,209x = 797,359.68
  5. Step 5: Solve for x
    x = 797,359.68/1,209
  6. Step 6: Final answer
    x = 659.52

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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.