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Finding the Fourth Proportional to 390.18, 586.08 and 343.20

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Solution

The fourth proportional to 390.18, 586.08 and 343.20 is: 515.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.18 : 586.08 = 343.20 : x
  2. Step 2: Convert to fraction form
    390.18/586.08 = 343.20/x
  3. Step 3: Cross multiply
    390.18x = 586.08 × 343.20
  4. Step 4: Simplify right side
    390.18x = 201,142.66
  5. Step 5: Solve for x
    x = 201,142.66/390.18
  6. Step 6: Final answer
    x = 515.51

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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.