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Finding the Fourth Proportional to 419.49, 579.15 and 315.72

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Solution

The fourth proportional to 419.49, 579.15 and 315.72 is: 435.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.49 : 579.15 = 315.72 : x
  2. Step 2: Convert to fraction form
    419.49/579.15 = 315.72/x
  3. Step 3: Cross multiply
    419.49x = 579.15 × 315.72
  4. Step 4: Simplify right side
    419.49x = 182,849.24
  5. Step 5: Solve for x
    x = 182,849.24/419.49
  6. Step 6: Final answer
    x = 435.88

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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.