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Finding the Fourth Proportional to 613.08, 918.78 and 287.76

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Solution

The fourth proportional to 613.08, 918.78 and 287.76 is: 431.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    613.08 : 918.78 = 287.76 : x
  2. Step 2: Convert to fraction form
    613.08/918.78 = 287.76/x
  3. Step 3: Cross multiply
    613.08x = 918.78 × 287.76
  4. Step 4: Simplify right side
    613.08x = 264,388.13
  5. Step 5: Solve for x
    x = 264,388.13/613.08
  6. Step 6: Final answer
    x = 431.25

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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.