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Finding the Fourth Proportional to 652.78, 978.90 and 257.41

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Solution

The fourth proportional to 652.78, 978.90 and 257.41 is: 386.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    652.78 : 978.90 = 257.41 : x
  2. Step 2: Convert to fraction form
    652.78/978.90 = 257.41/x
  3. Step 3: Cross multiply
    652.78x = 978.90 × 257.41
  4. Step 4: Simplify right side
    652.78x = 251,978.65
  5. Step 5: Solve for x
    x = 251,978.65/652.78
  6. Step 6: Final answer
    x = 386.01

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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.