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Finding the Fourth Proportional to 856.58, 1,285.14 and 279.32

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Solution

The fourth proportional to 856.58, 1,285.14 and 279.32 is: 419.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.58 : 1,285.14 = 279.32 : x
  2. Step 2: Convert to fraction form
    856.58/1,285.14 = 279.32/x
  3. Step 3: Cross multiply
    856.58x = 1,285.14 × 279.32
  4. Step 4: Simplify right side
    856.58x = 358,965.30
  5. Step 5: Solve for x
    x = 358,965.30/856.58
  6. Step 6: Final answer
    x = 419.07

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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.