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Finding the Fourth Proportional to 280.65, 418.47 and 260.15

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Solution

The fourth proportional to 280.65, 418.47 and 260.15 is: 387.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.65 : 418.47 = 260.15 : x
  2. Step 2: Convert to fraction form
    280.65/418.47 = 260.15/x
  3. Step 3: Cross multiply
    280.65x = 418.47 × 260.15
  4. Step 4: Simplify right side
    280.65x = 108,862.88
  5. Step 5: Solve for x
    x = 108,862.88/280.65
  6. Step 6: Final answer
    x = 387.90

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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.