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Finding the Fourth Proportional to 338.33, 509.81 and 278.80

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Solution

The fourth proportional to 338.33, 509.81 and 278.80 is: 420.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.33 : 509.81 = 278.80 : x
  2. Step 2: Convert to fraction form
    338.33/509.81 = 278.80/x
  3. Step 3: Cross multiply
    338.33x = 509.81 × 278.80
  4. Step 4: Simplify right side
    338.33x = 142,132.36
  5. Step 5: Solve for x
    x = 142,132.36/338.33
  6. Step 6: Final answer
    x = 420.10

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.