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Finding the Fourth Proportional to 540.79, 811.25 and 280.91

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Solution

The fourth proportional to 540.79, 811.25 and 280.91 is: 421.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    540.79 : 811.25 = 280.91 : x
  2. Step 2: Convert to fraction form
    540.79/811.25 = 280.91/x
  3. Step 3: Cross multiply
    540.79x = 811.25 × 280.91
  4. Step 4: Simplify right side
    540.79x = 227,886.83
  5. Step 5: Solve for x
    x = 227,886.83/540.79
  6. Step 6: Final answer
    x = 421.40

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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.