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Finding the Fourth Proportional to 419.65, 579.05 and 279.96

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Solution

The fourth proportional to 419.65, 579.05 and 279.96 is: 386.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.65 : 579.05 = 279.96 : x
  2. Step 2: Convert to fraction form
    419.65/579.05 = 279.96/x
  3. Step 3: Cross multiply
    419.65x = 579.05 × 279.96
  4. Step 4: Simplify right side
    419.65x = 162,108.32
  5. Step 5: Solve for x
    x = 162,108.32/419.65
  6. Step 6: Final answer
    x = 386.30

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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.