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Finding the Fourth Proportional to 398.64, 549.52 and 280.25

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Solution

The fourth proportional to 398.64, 549.52 and 280.25 is: 386.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.64 : 549.52 = 280.25 : x
  2. Step 2: Convert to fraction form
    398.64/549.52 = 280.25/x
  3. Step 3: Cross multiply
    398.64x = 549.52 × 280.25
  4. Step 4: Simplify right side
    398.64x = 153,999.53
  5. Step 5: Solve for x
    x = 153,999.53/398.64
  6. Step 6: Final answer
    x = 386.31

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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.