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Finding the Fourth Proportional to 800.10, 1,199.79 and 312.81

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Solution

The fourth proportional to 800.10, 1,199.79 and 312.81 is: 469.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.10 : 1,199.79 = 312.81 : x
  2. Step 2: Convert to fraction form
    800.10/1,199.79 = 312.81/x
  3. Step 3: Cross multiply
    800.10x = 1,199.79 × 312.81
  4. Step 4: Simplify right side
    800.10x = 375,306.31
  5. Step 5: Solve for x
    x = 375,306.31/800.10
  6. Step 6: Final answer
    x = 469.07

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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.