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Finding the Fourth Proportional to 397.84, 549.06 and 279.78

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Solution

The fourth proportional to 397.84, 549.06 and 279.78 is: 386.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    397.84 : 549.06 = 279.78 : x
  2. Step 2: Convert to fraction form
    397.84/549.06 = 279.78/x
  3. Step 3: Cross multiply
    397.84x = 549.06 × 279.78
  4. Step 4: Simplify right side
    397.84x = 153,616.01
  5. Step 5: Solve for x
    x = 153,616.01/397.84
  6. Step 6: Final answer
    x = 386.13

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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.