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Finding the Fourth Proportional to 390.79, 539.30 and 224.99

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Solution

The fourth proportional to 390.79, 539.30 and 224.99 is: 310.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.79 : 539.30 = 224.99 : x
  2. Step 2: Convert to fraction form
    390.79/539.30 = 224.99/x
  3. Step 3: Cross multiply
    390.79x = 539.30 × 224.99
  4. Step 4: Simplify right side
    390.79x = 121,333.29
  5. Step 5: Solve for x
    x = 121,333.29/390.79
  6. Step 6: Final answer
    x = 310.49

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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.