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Finding the Fourth Proportional to 307.71, 422.48 and 278.55

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Solution

The fourth proportional to 307.71, 422.48 and 278.55 is: 382.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    307.71 : 422.48 = 278.55 : x
  2. Step 2: Convert to fraction form
    307.71/422.48 = 278.55/x
  3. Step 3: Cross multiply
    307.71x = 422.48 × 278.55
  4. Step 4: Simplify right side
    307.71x = 117,682.50
  5. Step 5: Solve for x
    x = 117,682.50/307.71
  6. Step 6: Final answer
    x = 382.45

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.