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Finding the Fourth Proportional to 989.81, 1,483.78 and 340.09

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Solution

The fourth proportional to 989.81, 1,483.78 and 340.09 is: 509.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    989.81 : 1,483.78 = 340.09 : x
  2. Step 2: Convert to fraction form
    989.81/1,483.78 = 340.09/x
  3. Step 3: Cross multiply
    989.81x = 1,483.78 × 340.09
  4. Step 4: Simplify right side
    989.81x = 504,615.03
  5. Step 5: Solve for x
    x = 504,615.03/989.81
  6. Step 6: Final answer
    x = 509.81

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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.