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Finding the Fourth Proportional to 390.99, 586.17 and 228.81

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Solution

The fourth proportional to 390.99, 586.17 and 228.81 is: 343.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.99 : 586.17 = 228.81 : x
  2. Step 2: Convert to fraction form
    390.99/586.17 = 228.81/x
  3. Step 3: Cross multiply
    390.99x = 586.17 × 228.81
  4. Step 4: Simplify right side
    390.99x = 134,121.56
  5. Step 5: Solve for x
    x = 134,121.56/390.99
  6. Step 6: Final answer
    x = 343.03

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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.