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Finding the Fourth Proportional to 1,219.26, 1,828.04 and 780.78

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Solution

The fourth proportional to 1,219.26, 1,828.04 and 780.78 is: 1,170.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,219.26 : 1,828.04 = 780.78 : x
  2. Step 2: Convert to fraction form
    1,219.26/1,828.04 = 780.78/x
  3. Step 3: Cross multiply
    1,219.26x = 1,828.04 × 780.78
  4. Step 4: Simplify right side
    1,219.26x = 1,427,297.07
  5. Step 5: Solve for x
    x = 1,427,297.07/1,219.26
  6. Step 6: Final answer
    x = 1,170.63

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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.