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Finding the Fourth Proportional to 419.45, 579.04 and 279.80

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Solution

The fourth proportional to 419.45, 579.04 and 279.80 is: 386.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.45 : 579.04 = 279.80 : x
  2. Step 2: Convert to fraction form
    419.45/579.04 = 279.80/x
  3. Step 3: Cross multiply
    419.45x = 579.04 × 279.80
  4. Step 4: Simplify right side
    419.45x = 162,011.10
  5. Step 5: Solve for x
    x = 162,011.10/419.45
  6. Step 6: Final answer
    x = 386.25

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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.