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Finding the Fourth Proportional to 278.80, 420.26 and 271.60

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Solution

The fourth proportional to 278.80, 420.26 and 271.60 is: 409.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.80 : 420.26 = 271.60 : x
  2. Step 2: Convert to fraction form
    278.80/420.26 = 271.60/x
  3. Step 3: Cross multiply
    278.80x = 420.26 × 271.60
  4. Step 4: Simplify right side
    278.80x = 114,142.62
  5. Step 5: Solve for x
    x = 114,142.62/278.80
  6. Step 6: Final answer
    x = 409.41

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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.