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Finding the Fourth Proportional to 312.05, 470.18 and 278.89

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Solution

The fourth proportional to 312.05, 470.18 and 278.89 is: 420.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.05 : 470.18 = 278.89 : x
  2. Step 2: Convert to fraction form
    312.05/470.18 = 278.89/x
  3. Step 3: Cross multiply
    312.05x = 470.18 × 278.89
  4. Step 4: Simplify right side
    312.05x = 131,128.02
  5. Step 5: Solve for x
    x = 131,128.02/312.05
  6. Step 6: Final answer
    x = 420.21

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.