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Finding the Fourth Proportional to 378.06, 521.39 and 280.06

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Solution

The fourth proportional to 378.06, 521.39 and 280.06 is: 386.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.06 : 521.39 = 280.06 : x
  2. Step 2: Convert to fraction form
    378.06/521.39 = 280.06/x
  3. Step 3: Cross multiply
    378.06x = 521.39 × 280.06
  4. Step 4: Simplify right side
    378.06x = 146,020.48
  5. Step 5: Solve for x
    x = 146,020.48/378.06
  6. Step 6: Final answer
    x = 386.24

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.