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Finding the Fourth Proportional to 340.40, 509.59 and 218.30

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Solution

The fourth proportional to 340.40, 509.59 and 218.30 is: 326.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    340.40 : 509.59 = 218.30 : x
  2. Step 2: Convert to fraction form
    340.40/509.59 = 218.30/x
  3. Step 3: Cross multiply
    340.40x = 509.59 × 218.30
  4. Step 4: Simplify right side
    340.40x = 111,241.22
  5. Step 5: Solve for x
    x = 111,241.22/340.40
  6. Step 6: Final answer
    x = 326.79

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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.