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Finding the Fourth Proportional to 307.87, 425.15 and 278.71

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Solution

The fourth proportional to 307.87, 425.15 and 278.71 is: 384.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    307.87 : 425.15 = 278.71 : x
  2. Step 2: Convert to fraction form
    307.87/425.15 = 278.71/x
  3. Step 3: Cross multiply
    307.87x = 425.15 × 278.71
  4. Step 4: Simplify right side
    307.87x = 118,492.15
  5. Step 5: Solve for x
    x = 118,492.15/307.87
  6. Step 6: Final answer
    x = 384.88

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.