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Finding the Fourth Proportional to 509.40, 764.20 and 216.90

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Solution

The fourth proportional to 509.40, 764.20 and 216.90 is: 325.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.40 : 764.20 = 216.90 : x
  2. Step 2: Convert to fraction form
    509.40/764.20 = 216.90/x
  3. Step 3: Cross multiply
    509.40x = 764.20 × 216.90
  4. Step 4: Simplify right side
    509.40x = 165,754.09
  5. Step 5: Solve for x
    x = 165,754.09/509.40
  6. Step 6: Final answer
    x = 325.39

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1.5x scale

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.