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Finding the Fourth Proportional to 989.84, 1,485 and 340.60

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Solution

The fourth proportional to 989.84, 1,485 and 340.60 is: 510.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    989.84 : 1,485 = 340.60 : x
  2. Step 2: Convert to fraction form
    989.84/1,485 = 340.60/x
  3. Step 3: Cross multiply
    989.84x = 1,485 × 340.60
  4. Step 4: Simplify right side
    989.84x = 505,791.00
  5. Step 5: Solve for x
    x = 505,791.00/989.84
  6. Step 6: Final answer
    x = 510.98

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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.