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Finding the Fourth Proportional to 390.02, 585.09 and 253.19

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Solution

The fourth proportional to 390.02, 585.09 and 253.19 is: 379.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.02 : 585.09 = 253.19 : x
  2. Step 2: Convert to fraction form
    390.02/585.09 = 253.19/x
  3. Step 3: Cross multiply
    390.02x = 585.09 × 253.19
  4. Step 4: Simplify right side
    390.02x = 148,140.40
  5. Step 5: Solve for x
    x = 148,140.40/390.02
  6. Step 6: Final answer
    x = 379.83

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.