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Finding the Fourth Proportional to 620.38, 930.30 and 312.39

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Solution

The fourth proportional to 620.38, 930.30 and 312.39 is: 468.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.38 : 930.30 = 312.39 : x
  2. Step 2: Convert to fraction form
    620.38/930.30 = 312.39/x
  3. Step 3: Cross multiply
    620.38x = 930.30 × 312.39
  4. Step 4: Simplify right side
    620.38x = 290,617.00
  5. Step 5: Solve for x
    x = 290,617.00/620.38
  6. Step 6: Final answer
    x = 468.45

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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.