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Finding the Fourth Proportional to 500.65, 690.79 and 290.70

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Solution

The fourth proportional to 500.65, 690.79 and 290.70 is: 401.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.65 : 690.79 = 290.70 : x
  2. Step 2: Convert to fraction form
    500.65/690.79 = 290.70/x
  3. Step 3: Cross multiply
    500.65x = 690.79 × 290.70
  4. Step 4: Simplify right side
    500.65x = 200,813.97
  5. Step 5: Solve for x
    x = 200,813.97/500.65
  6. Step 6: Final answer
    x = 401.11

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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.