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Finding the Fourth Proportional to 400.80, 549.48 and 387.84

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Solution

The fourth proportional to 400.80, 549.48 and 387.84 is: 531.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    400.80 : 549.48 = 387.84 : x
  2. Step 2: Convert to fraction form
    400.80/549.48 = 387.84/x
  3. Step 3: Cross multiply
    400.80x = 549.48 × 387.84
  4. Step 4: Simplify right side
    400.80x = 213,110.32
  5. Step 5: Solve for x
    x = 213,110.32/400.80
  6. Step 6: Final answer
    x = 531.71

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.