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Finding the Fourth Proportional to 621.09, 930.96 and 312.75

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Solution

The fourth proportional to 621.09, 930.96 and 312.75 is: 468.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.09 : 930.96 = 312.75 : x
  2. Step 2: Convert to fraction form
    621.09/930.96 = 312.75/x
  3. Step 3: Cross multiply
    621.09x = 930.96 × 312.75
  4. Step 4: Simplify right side
    621.09x = 291,157.74
  5. Step 5: Solve for x
    x = 291,157.74/621.09
  6. Step 6: Final answer
    x = 468.79

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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.