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Finding the Fourth Proportional to 856.50, 1,281.98 and 445.05

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Solution

The fourth proportional to 856.50, 1,281.98 and 445.05 is: 666.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.50 : 1,281.98 = 445.05 : x
  2. Step 2: Convert to fraction form
    856.50/1,281.98 = 445.05/x
  3. Step 3: Cross multiply
    856.50x = 1,281.98 × 445.05
  4. Step 4: Simplify right side
    856.50x = 570,542.97
  5. Step 5: Solve for x
    x = 570,542.97/856.50
  6. Step 6: Final answer
    x = 666.13

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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.