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Finding the Fourth Proportional to 280.48, 420.78 and 158.80

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Solution

The fourth proportional to 280.48, 420.78 and 158.80 is: 238.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.48 : 420.78 = 158.80 : x
  2. Step 2: Convert to fraction form
    280.48/420.78 = 158.80/x
  3. Step 3: Cross multiply
    280.48x = 420.78 × 158.80
  4. Step 4: Simplify right side
    280.48x = 66,819.86
  5. Step 5: Solve for x
    x = 66,819.86/280.48
  6. Step 6: Final answer
    x = 238.23

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.