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Finding the Fourth Proportional to 312.68, 429.18 and 299.31

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Solution

The fourth proportional to 312.68, 429.18 and 299.31 is: 410.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.68 : 429.18 = 299.31 : x
  2. Step 2: Convert to fraction form
    312.68/429.18 = 299.31/x
  3. Step 3: Cross multiply
    312.68x = 429.18 × 299.31
  4. Step 4: Simplify right side
    312.68x = 128,457.87
  5. Step 5: Solve for x
    x = 128,457.87/312.68
  6. Step 6: Final answer
    x = 410.84

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.