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Finding the Fourth Proportional to 279.84, 386.20 and 210.05

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Solution

The fourth proportional to 279.84, 386.20 and 210.05 is: 289.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.84 : 386.20 = 210.05 : x
  2. Step 2: Convert to fraction form
    279.84/386.20 = 210.05/x
  3. Step 3: Cross multiply
    279.84x = 386.20 × 210.05
  4. Step 4: Simplify right side
    279.84x = 81,121.31
  5. Step 5: Solve for x
    x = 81,121.31/279.84
  6. Step 6: Final answer
    x = 289.88

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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.