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Finding the Fourth Proportional to 856.65, 1,285.64 and 394.63

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Solution

The fourth proportional to 856.65, 1,285.64 and 394.63 is: 592.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.65 : 1,285.64 = 394.63 : x
  2. Step 2: Convert to fraction form
    856.65/1,285.64 = 394.63/x
  3. Step 3: Cross multiply
    856.65x = 1,285.64 × 394.63
  4. Step 4: Simplify right side
    856.65x = 507,352.11
  5. Step 5: Solve for x
    x = 507,352.11/856.65
  6. Step 6: Final answer
    x = 592.25

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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.