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Finding the Fourth Proportional to 500.34, 690.40 and 421.36

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Solution

The fourth proportional to 500.34, 690.40 and 421.36 is: 581.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.34 : 690.40 = 421.36 : x
  2. Step 2: Convert to fraction form
    500.34/690.40 = 421.36/x
  3. Step 3: Cross multiply
    500.34x = 690.40 × 421.36
  4. Step 4: Simplify right side
    500.34x = 290,906.94
  5. Step 5: Solve for x
    x = 290,906.94/500.34
  6. Step 6: Final answer
    x = 581.42

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1.5x scale

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.