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Finding the Fourth Proportional to 340.80, 511.20 and 218.76

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Solution

The fourth proportional to 340.80, 511.20 and 218.76 is: 328.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    340.80 : 511.20 = 218.76 : x
  2. Step 2: Convert to fraction form
    340.80/511.20 = 218.76/x
  3. Step 3: Cross multiply
    340.80x = 511.20 × 218.76
  4. Step 4: Simplify right side
    340.80x = 111,830.11
  5. Step 5: Solve for x
    x = 111,830.11/340.80
  6. Step 6: Final answer
    x = 328.14

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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.