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Finding the Fourth Proportional to 420.64, 630.96 and 228.64

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Solution

The fourth proportional to 420.64, 630.96 and 228.64 is: 342.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.64 : 630.96 = 228.64 : x
  2. Step 2: Convert to fraction form
    420.64/630.96 = 228.64/x
  3. Step 3: Cross multiply
    420.64x = 630.96 × 228.64
  4. Step 4: Simplify right side
    420.64x = 144,262.69
  5. Step 5: Solve for x
    x = 144,262.69/420.64
  6. Step 6: Final answer
    x = 342.96

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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.