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Finding the Fourth Proportional to 1,280.50, 1,920.87 and 343.43

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Solution

The fourth proportional to 1,280.50, 1,920.87 and 343.43 is: 515.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.50 : 1,920.87 = 343.43 : x
  2. Step 2: Convert to fraction form
    1,280.50/1,920.87 = 343.43/x
  3. Step 3: Cross multiply
    1,280.50x = 1,920.87 × 343.43
  4. Step 4: Simplify right side
    1,280.50x = 659,681.98
  5. Step 5: Solve for x
    x = 659,681.98/1,280.50
  6. Step 6: Final answer
    x = 515.18

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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.