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Finding the Fourth Proportional to 540.80, 811.40 and 216.20

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Solution

The fourth proportional to 540.80, 811.40 and 216.20 is: 324.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    540.80 : 811.40 = 216.20 : x
  2. Step 2: Convert to fraction form
    540.80/811.40 = 216.20/x
  3. Step 3: Cross multiply
    540.80x = 811.40 × 216.20
  4. Step 4: Simplify right side
    540.80x = 175,421.16
  5. Step 5: Solve for x
    x = 175,421.16/540.80
  6. Step 6: Final answer
    x = 324.38

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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.