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Finding the Fourth Proportional to 1,200.39, 1,800.84 and 430.89

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Solution

The fourth proportional to 1,200.39, 1,800.84 and 430.89 is: 646.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,200.39 : 1,800.84 = 430.89 : x
  2. Step 2: Convert to fraction form
    1,200.39/1,800.84 = 430.89/x
  3. Step 3: Cross multiply
    1,200.39x = 1,800.84 × 430.89
  4. Step 4: Simplify right side
    1,200.39x = 775,963.95
  5. Step 5: Solve for x
    x = 775,963.95/1,200.39
  6. Step 6: Final answer
    x = 646.43

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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.