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Finding the Fourth Proportional to 856.50, 1,284.96 and 279.38

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Solution

The fourth proportional to 856.50, 1,284.96 and 279.38 is: 419.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.50 : 1,284.96 = 279.38 : x
  2. Step 2: Convert to fraction form
    856.50/1,284.96 = 279.38/x
  3. Step 3: Cross multiply
    856.50x = 1,284.96 × 279.38
  4. Step 4: Simplify right side
    856.50x = 358,992.12
  5. Step 5: Solve for x
    x = 358,992.12/856.50
  6. Step 6: Final answer
    x = 419.14

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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.