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Finding the Fourth Proportional to 398.49, 549.27 and 305.07

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Solution

The fourth proportional to 398.49, 549.27 and 305.07 is: 420.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.49 : 549.27 = 305.07 : x
  2. Step 2: Convert to fraction form
    398.49/549.27 = 305.07/x
  3. Step 3: Cross multiply
    398.49x = 549.27 × 305.07
  4. Step 4: Simplify right side
    398.49x = 167,565.80
  5. Step 5: Solve for x
    x = 167,565.80/398.49
  6. Step 6: Final answer
    x = 420.50

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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.