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Finding the Fourth Proportional to 612.68, 918.78 and 320.09

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Solution

The fourth proportional to 612.68, 918.78 and 320.09 is: 480.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.68 : 918.78 = 320.09 : x
  2. Step 2: Convert to fraction form
    612.68/918.78 = 320.09/x
  3. Step 3: Cross multiply
    612.68x = 918.78 × 320.09
  4. Step 4: Simplify right side
    612.68x = 294,092.29
  5. Step 5: Solve for x
    x = 294,092.29/612.68
  6. Step 6: Final answer
    x = 480.01

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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.