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Finding the Fourth Proportional to 338.80, 510.32 and 278.68

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Solution

The fourth proportional to 338.80, 510.32 and 278.68 is: 419.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.80 : 510.32 = 278.68 : x
  2. Step 2: Convert to fraction form
    338.80/510.32 = 278.68/x
  3. Step 3: Cross multiply
    338.80x = 510.32 × 278.68
  4. Step 4: Simplify right side
    338.80x = 142,215.98
  5. Step 5: Solve for x
    x = 142,215.98/338.80
  6. Step 6: Final answer
    x = 419.76

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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.