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Finding the Fourth Proportional to 340.80, 512.40 and 280.32

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Solution

The fourth proportional to 340.80, 512.40 and 280.32 is: 421.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    340.80 : 512.40 = 280.32 : x
  2. Step 2: Convert to fraction form
    340.80/512.40 = 280.32/x
  3. Step 3: Cross multiply
    340.80x = 512.40 × 280.32
  4. Step 4: Simplify right side
    340.80x = 143,635.97
  5. Step 5: Solve for x
    x = 143,635.97/340.80
  6. Step 6: Final answer
    x = 421.47

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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.