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Finding the Fourth Proportional to 317.50, 438.96 and 303.90

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Solution

The fourth proportional to 317.50, 438.96 and 303.90 is: 420.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    317.50 : 438.96 = 303.90 : x
  2. Step 2: Convert to fraction form
    317.50/438.96 = 303.90/x
  3. Step 3: Cross multiply
    317.50x = 438.96 × 303.90
  4. Step 4: Simplify right side
    317.50x = 133,399.94
  5. Step 5: Solve for x
    x = 133,399.94/317.50
  6. Step 6: Final answer
    x = 420.16

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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.