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Finding the Fourth Proportional to 856.20, 1,284.27 and 279.07

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Solution

The fourth proportional to 856.20, 1,284.27 and 279.07 is: 418.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.20 : 1,284.27 = 279.07 : x
  2. Step 2: Convert to fraction form
    856.20/1,284.27 = 279.07/x
  3. Step 3: Cross multiply
    856.20x = 1,284.27 × 279.07
  4. Step 4: Simplify right side
    856.20x = 358,401.23
  5. Step 5: Solve for x
    x = 358,401.23/856.20
  6. Step 6: Final answer
    x = 418.60

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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.