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Finding the Fourth Proportional to 420.64, 579.84 and 316.96

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Solution

The fourth proportional to 420.64, 579.84 and 316.96 is: 436.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.64 : 579.84 = 316.96 : x
  2. Step 2: Convert to fraction form
    420.64/579.84 = 316.96/x
  3. Step 3: Cross multiply
    420.64x = 579.84 × 316.96
  4. Step 4: Simplify right side
    420.64x = 183,786.09
  5. Step 5: Solve for x
    x = 183,786.09/420.64
  6. Step 6: Final answer
    x = 436.92

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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.