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Finding the Fourth Proportional to 619.92, 856.52 and 490

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Solution

The fourth proportional to 619.92, 856.52 and 490 is: 677.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.92 : 856.52 = 490 : x
  2. Step 2: Convert to fraction form
    619.92/856.52 = 490/x
  3. Step 3: Cross multiply
    619.92x = 856.52 × 490
  4. Step 4: Simplify right side
    619.92x = 419,694.80
  5. Step 5: Solve for x
    x = 419,694.80/619.92
  6. Step 6: Final answer
    x = 677.01

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.