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Finding the Fourth Proportional to 1,820.31, 2,728.63 and 780.99

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Solution

The fourth proportional to 1,820.31, 2,728.63 and 780.99 is: 1,170.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,820.31 : 2,728.63 = 780.99 : x
  2. Step 2: Convert to fraction form
    1,820.31/2,728.63 = 780.99/x
  3. Step 3: Cross multiply
    1,820.31x = 2,728.63 × 780.99
  4. Step 4: Simplify right side
    1,820.31x = 2,131,032.74
  5. Step 5: Solve for x
    x = 2,131,032.74/1,820.31
  6. Step 6: Final answer
    x = 1,170.70

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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.