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Finding the Fourth Proportional to 279.80, 386.12 and 161.81

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Solution

The fourth proportional to 279.80, 386.12 and 161.81 is: 223.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.80 : 386.12 = 161.81 : x
  2. Step 2: Convert to fraction form
    279.80/386.12 = 161.81/x
  3. Step 3: Cross multiply
    279.80x = 386.12 × 161.81
  4. Step 4: Simplify right side
    279.80x = 62,478.08
  5. Step 5: Solve for x
    x = 62,478.08/279.80
  6. Step 6: Final answer
    x = 223.30

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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.