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Finding the Fourth Proportional to 620.88, 931.31 and 278.88

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Solution

The fourth proportional to 620.88, 931.31 and 278.88 is: 418.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.88 : 931.31 = 278.88 : x
  2. Step 2: Convert to fraction form
    620.88/931.31 = 278.88/x
  3. Step 3: Cross multiply
    620.88x = 931.31 × 278.88
  4. Step 4: Simplify right side
    620.88x = 259,723.73
  5. Step 5: Solve for x
    x = 259,723.73/620.88
  6. Step 6: Final answer
    x = 418.32

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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.