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Finding the Fourth Proportional to 540.90, 811.58 and 387.81

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Solution

The fourth proportional to 540.90, 811.58 and 387.81 is: 581.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    540.90 : 811.58 = 387.81 : x
  2. Step 2: Convert to fraction form
    540.90/811.58 = 387.81/x
  3. Step 3: Cross multiply
    540.90x = 811.58 × 387.81
  4. Step 4: Simplify right side
    540.90x = 314,736.90
  5. Step 5: Solve for x
    x = 314,736.90/540.90
  6. Step 6: Final answer
    x = 581.88

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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.