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Finding the Fourth Proportional to 500.08, 690.05 and 311.08

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Solution

The fourth proportional to 500.08, 690.05 and 311.08 is: 429.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.08 : 690.05 = 311.08 : x
  2. Step 2: Convert to fraction form
    500.08/690.05 = 311.08/x
  3. Step 3: Cross multiply
    500.08x = 690.05 × 311.08
  4. Step 4: Simplify right side
    500.08x = 214,659.81
  5. Step 5: Solve for x
    x = 214,659.81/500.08
  6. Step 6: Final answer
    x = 429.25

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.