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Finding the Fourth Proportional to 378, 521.64 and 280.26

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Solution

The fourth proportional to 378, 521.64 and 280.26 is: 386.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    378 : 521.64 = 280.26 : x
  2. Step 2: Convert to fraction form
    378/521.64 = 280.26/x
  3. Step 3: Cross multiply
    378x = 521.64 × 280.26
  4. Step 4: Simplify right side
    378x = 146,194.83
  5. Step 5: Solve for x
    x = 146,194.83/378
  6. Step 6: Final answer
    x = 386.76

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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.