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Finding the Fourth Proportional to 856.09, 1,284.12 and 239.79

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Solution

The fourth proportional to 856.09, 1,284.12 and 239.79 is: 359.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.09 : 1,284.12 = 239.79 : x
  2. Step 2: Convert to fraction form
    856.09/1,284.12 = 239.79/x
  3. Step 3: Cross multiply
    856.09x = 1,284.12 × 239.79
  4. Step 4: Simplify right side
    856.09x = 307,912.71
  5. Step 5: Solve for x
    x = 307,912.71/856.09
  6. Step 6: Final answer
    x = 359.67

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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.