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Finding the Fourth Proportional to 500.72, 690.65 and 388.97

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Solution

The fourth proportional to 500.72, 690.65 and 388.97 is: 536.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.72 : 690.65 = 388.97 : x
  2. Step 2: Convert to fraction form
    500.72/690.65 = 388.97/x
  3. Step 3: Cross multiply
    500.72x = 690.65 × 388.97
  4. Step 4: Simplify right side
    500.72x = 268,642.13
  5. Step 5: Solve for x
    x = 268,642.13/500.72
  6. Step 6: Final answer
    x = 536.51

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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.