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Finding the Fourth Proportional to 410.39, 615.39 and 280.43

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Solution

The fourth proportional to 410.39, 615.39 and 280.43 is: 420.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    410.39 : 615.39 = 280.43 : x
  2. Step 2: Convert to fraction form
    410.39/615.39 = 280.43/x
  3. Step 3: Cross multiply
    410.39x = 615.39 × 280.43
  4. Step 4: Simplify right side
    410.39x = 172,570.74
  5. Step 5: Solve for x
    x = 172,570.74/410.39
  6. Step 6: Final answer
    x = 420.51

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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.