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Finding the Fourth Proportional to 343.40, 514.50 and 285.99

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Solution

The fourth proportional to 343.40, 514.50 and 285.99 is: 428.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    343.40 : 514.50 = 285.99 : x
  2. Step 2: Convert to fraction form
    343.40/514.50 = 285.99/x
  3. Step 3: Cross multiply
    343.40x = 514.50 × 285.99
  4. Step 4: Simplify right side
    343.40x = 147,140.43
  5. Step 5: Solve for x
    x = 147,140.43/343.40
  6. Step 6: Final answer
    x = 428.48

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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.