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Finding the Fourth Proportional to 1,320.49, 1,980.76 and 499.15

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Solution

The fourth proportional to 1,320.49, 1,980.76 and 499.15 is: 748.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,320.49 : 1,980.76 = 499.15 : x
  2. Step 2: Convert to fraction form
    1,320.49/1,980.76 = 499.15/x
  3. Step 3: Cross multiply
    1,320.49x = 1,980.76 × 499.15
  4. Step 4: Simplify right side
    1,320.49x = 988,696.35
  5. Step 5: Solve for x
    x = 988,696.35/1,320.49
  6. Step 6: Final answer
    x = 748.73

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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.