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Finding the Fourth Proportional to 1,980.49, 2,970.50 and 519.75

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Solution

The fourth proportional to 1,980.49, 2,970.50 and 519.75 is: 779.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,980.49 : 2,970.50 = 519.75 : x
  2. Step 2: Convert to fraction form
    1,980.49/2,970.50 = 519.75/x
  3. Step 3: Cross multiply
    1,980.49x = 2,970.50 × 519.75
  4. Step 4: Simplify right side
    1,980.49x = 1,543,917.38
  5. Step 5: Solve for x
    x = 1,543,917.38/1,980.49
  6. Step 6: Final answer
    x = 779.56

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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.