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Finding the Fourth Proportional to 509.63, 764.31 and 221

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Solution

The fourth proportional to 509.63, 764.31 and 221 is: 331.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.63 : 764.31 = 221 : x
  2. Step 2: Convert to fraction form
    509.63/764.31 = 221/x
  3. Step 3: Cross multiply
    509.63x = 764.31 × 221
  4. Step 4: Simplify right side
    509.63x = 168,912.51
  5. Step 5: Solve for x
    x = 168,912.51/509.63
  6. Step 6: Final answer
    x = 331.44

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Double scale
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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.