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Finding the Fourth Proportional to 280.42, 418.33 and 260.78

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Solution

The fourth proportional to 280.42, 418.33 and 260.78 is: 389.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.42 : 418.33 = 260.78 : x
  2. Step 2: Convert to fraction form
    280.42/418.33 = 260.78/x
  3. Step 3: Cross multiply
    280.42x = 418.33 × 260.78
  4. Step 4: Simplify right side
    280.42x = 109,092.10
  5. Step 5: Solve for x
    x = 109,092.10/280.42
  6. Step 6: Final answer
    x = 389.03

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.